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Modeled on the HST approach, up to 5% of the total Chandra observing time will be reserved for CXC Director's Discretionary Time(DDT) observations. This allocation of time shall include unanticipated, non-peer reviewed TOOs.

Short descriptions of each form and field are below. This file is ordered by form (Cover, General, Target, Constraint). Form names are prefixed with * and field names are prefixed with **. Fields in this file are listed in the same order as found on the hardcopy forms, mosaic forms, and the E-mail talker forms.

* COVER PAGE

Your personal details (name, address, telephone number, etc.) and the proposal name and number of targets.

** Principal Investigator Title

This item and the next 3 are combined on the hardcopy form to identify the Principal Investigator(P.I.).
P.I. title (Dr, Ms, Mr, etc.). This does NOT refer to one's job description (ie: "postdoc").
Maximum of 20 characters.

** First Name

P.I. first name.
Maximum of 20 characters. Required.

** Middle Name or Initial

Another name or initials of P.I..
Maximum of 20 characters.

** Last Name

P.I. last name.
Maximum of 25 characters. Required.

** Department

Department of P.I. at the Institute.
Maximum of 100 characters.

** Institute

P.I. Institute. Use your internet browser's Edit, Copy and Paste functions to place your selection from the Institute list in the RPS window.

If your institution is not on this list, just type the Institute in this field. A warning will be displayed when the RPS form is verified or submitted. This warning does NOT affect the submission of your proposal.
Maximum of 100 characters. Required.

** Address/Street

The first line of the Institute address, ie Street, any number within it,etc.
Maximum of 30 characters.

** Mail Stop

P.I.'s mail stop at the Institute, if any.
Maximum of 30 characters.

** City/Town

Institute's Town or City.
Maximum of 30 characters.

** State/Province

The name of the state or province of the Institute.
Maximum of 30 characters.

** Zip/Postal Code

The Institute's post code, ZIP code or equivalent.
Maximum of 10 characters.

** Country

The default is USA. Below is the list of accepted country designations:
ARGENTINA       AUSTRALIA       AUSTRIA         BELGIUM        
BRAZIL BULGARIA CANADA CHILE
CHINA CZECH DENMARK ESTONIA
FINLAND FRANCE GERMANY GREECE
HONGKONG HUNGARY INDIA INDONESIA
IRAN IRELAND ISRAEL ITALY
JAPAN KOREA LATVIA LITHUANIA
MEXICO NETH NIGERIA NORWAY
NZ PERU POLAND PORTUGAL
ROMANIA RUSSIA SCOTLAND S AFRICA
SPAIN SWEDEN SWITZ TAIWAN
TURKEY UK UKRAINE USA
VENEZUELA      

If your country is not on this list, please contact CXC HelpDesk
Maximum of 30 characters. Required.

** Telephone

P.I. telephone number, plus any extension.
Maximum of 15 characters. Required.

** Fax

P.I. Fax number, if available.
Maximum of 15 characters.

** E-mail Address

P.I. E-mail address. An E-mail receipt will be sent to this address within 24 hours of the electronic submission of your proposal. Please make sure this is entered correctly.
Maximum of 50 characters. Required.

** Subject Category

The type of object(s) to be viewed in the Proposal. The categories are:
Solar System
Stars and WD
WD Binaries and CV
BH and NS Binaries
SN, SNR and Isolated NS
Normal Galaxies: Diffuse Emission
Normal Galaxies: X-ray Populations
Active Galaxies and Quasars
Clusters of Galaxies
Extragalactic Diffuse Emission and Surveys
Galactic Diffuse Emission and Surveys
Required.

** Proposal Type

DDT - Director's Discretionary Time
CAL - Calibration

RPS is being used by all Chandra groups as the input to the observation database, so the Proposal Type is important. General Observers (GO's) should use the 'DDT' type. The Proposal Type of Calibration is to be used only by CXC. No proposal from non-CXC personnel can be accepted that requests a Calibration observation. Required.

** Proprietary Rights

The default is no proprietary data rights. 'No proprietary rights' means that the data flows directly into the archive. Valid DDT options are: 
No proprietary rights (default)
Discretionary proprietary rights (0-3 months)
Required.

**Justification of Request for Proprietary Rights

Justify request for discretionary proprietary rights. This field is required if you wish to retain proprietary rights.
Maximum of 200 characters. Characters beyond this limit will be truncated.

** Data Distribution Medium

Indicates the preferred distribution method for the PI's data. Options are: 
    WWW Only        -  No other medium selected, default to WWW access
    CD-ROM,zipped   -  650 MB CD-ROM with data compression
    CD-ROM,unzipped -  650 MB CD-ROM with no data compression
    4GBDAT          -  4 GB 4 mm DAT
    2GBDAT          -  2 GB 4 mm DAT
    5GB8MM          -  5 GB 8 mm Exabyte
    2GB8MM          -  2 GB 8 mm Exabyte
Note that for CD-ROMs, if 'CD-ROM,unzipped' is chosen and the data is too large to fit on the CD-ROM, the data will be zipped. If the data is too large to fit on a CD-ROM when zipped, the data will be sent on '4GB 4mm DAT' tape. Required.

** Proposal Title

The title of the proposal.
Maximum of 120 characters. Required.

* GENERAL PAGE

Co-Investigator(CoI) information and proposal justifications.

** Is the Co-I doing observing, rather than the PI?

Logical value indicating if the Co-I listed is also the person who will primarily carry out the observations. This should be used for PIs who may be difficult to reach and for situations when a graduate student or post-doc is to be considered the "real" PI. The default is 'N'.

** Co-Investigator First Name

First Name for Co-Investigator Contact.
Maximum of 20 characters.

** Co-Investigator Last Name

Last Name for Co-Investigator Contact.
Maximum of 25 characters.

** Co-Investigator Telephone

Telphone number of the Co-Investigator Contact.
Maximum of 24 characters.

** Co-Investigator E-Mail Address

E-mail address for the Co-Investigator Contact.
Maximum of 50 characters.

** 24 Hour Contact Information

Please enter additional 24-hour contact information. The contact information should not be only the observer's daytime office number, but provide home phones, cell phones, and any additional information such as which contact information to use for what days/times.
Required for Fast and Medium response times.
Maximum of 255 characters.

** Scientific Justification

Please provide a compelling scientific case why Chandra should carry out this program.
Maxium of 1000 characters. Characters beyond this limited will be truncated. Required.

** Justification for this Particular Target

Please state why this particular target should be observed, i.e., why it is a good example of the phenomena addressed in the proposal.
Maximum of 200 characters. Characters beyond this limit will be truncated. Required.

** Why can't the observation wait for the next NRA?

Please state why it is necessary to interrupt the approved observation schedule to carry out this proposal now rather than wait for the next NRA.
Maximum of 400 characters. Characters beyond this limit will be truncated. Required.

** Likelihood of Detection, Duration, and Recurrence of Transient Behavior

Please provide estimates of a) how likely it is that Chandra will observe the transient behavior; b) the duration of the transient behavior; c) its likelihood of recurrence.
Maximum of 300 characters. Characters beyond this limit will be truncated. Required.

** Response Time Requested

Please select the response time requested for this observation and then state the justification in the Justification of Response Time field. Options are: 
Slow      > 30 Days
Medium    >= 3 Days  and <= 30 Days
Fast      < 3 Days
Required.

** Justification of Response Time

Please justify the response time requested. Should it be observed as soon as possible, or in, say ten days' time? The Chandra team, upon receipt of an RFO, will make the decision whether to go to the target. Agreement results in implementation, without further consultation with the PI. Therefore, please make sure that your RFO includes all information required to actually plan and schedule the entire observation, as you may not have an opportunity for additional feedback or information before the observation occurs.
Maximum of 400 characters. Characters beyond this limit will be truncated. Required.

Have you/Co-Is requested XMM DDT time for this/similar proposal?"

Please select Y if you have also requested XMM DDT time for this or a similar proposal.

If yes, please indicate status of XMM request

Please state the results of your XMM DDT request. Maximum of 255 characters. Characters beyond this limit will be truncated.

**Have you/Co-Is ever submitted similar/related proposals to a Chandra NRA?

Please select 'Y' if this request (or a similar one) has been submitted during a previous NRA. Default is 'N'. Required.

**If yes, please indicate cycle(s), PI name and status.

Please state the cycle(s) during which this observation has been previously submitted, the PI name and the status of each proposal, whether accepted/rejected and, if the former, completed/in progress.
Maximum of 200 characters. Characters beyond this limit will be truncated.

* TARGET PAGE

The page contains the details that need to be filled in for each different target. If the proposer will request more than one instrument, each instrument should be considered a "separate" target.

** Do you want to delete this target?

The default is 'N'(No). The default should be changed only if a particular target is to be removed. A target is deleted by setting this parameter to 'Y'(Yes) and clicking on the "Delete Target" button at the top or bottom of the RPS form. Please note that when a target is deleted, the remaining targets will need to be re-numbered accordingly so that there is no missing number.

** Target Number

The number of the target. Since the number is used to show the Peer Review the observing priority of one target relative to another, you may wish to change these around. However, the final proposal must contain a sequence of target numbers from 1 to the total number of primary targets. Valid range is 1 - 999. Required.

** Target Description

Please select one or more descriptive keywords pertaining to this target and/or to your science goals. Be inclusive; your selections may be used for preliminary matching of proposals to reviewers, and also for archive searches. Many of these keywords are in common with HST.

To select multiple items, click on each item while holding the Ctrl key. Browsers and keyboards may vary so try the Shift or Alt keys if the Ctrl key does not work. For email users, the keywords must be separated by a semicolon (;). Required.

** Target Name

Targets are searched in the database by common name which should be used as the name (NGC 4051). In the absence of a common name, please use IAU-sanctioned names. *Append* any additional target "name" info (e.g., NGC 4051 field 2).
Maximum of 30 characters. Required for all except Solar System Object

** Solar System Object

The name of the Solar System Object to be observed, from the following choices: None, Asteroid, Comet, Earth, Moon, Mars, Jupiter, Venus, Saturn, Neptune, Pluto, or Uranus.

The default is 'None'. Observations of moving solar system objects are done with a sequence of pointed observations, with the object moving through the field of view during each dwell period. The sequence of pointings will be derived from the object ephemeris to ensure that the object remains within 5' of the Chandra line-of-sight. Most solar system objects move slowly enough so that a single pointing will suffice. Should your observation be selected then the CXC will work with you to produce an observation that both meets your scientific objectives and optimizes the use of Chandra.

** R.A.

The Right Ascension of the source in mandatory J2000 coordinate system. Offsets from this position may be specified using the Y/Z Detector Offset field. The standard format is HH MM SS.S - hours, minutes, seconds, separated by spaces. Alternatively, it may be entered as degrees (DDD.DDDDDD), in which case it will be converted to sexagesimal during verification. The seconds may be entered as a real value with tenths (i.e., SS.S).
Required.

** Dec.

The declination of the source in mandatory J2000 coordinate system. Offsets from this position may be specified using the Y/Z Detector Offset field. The standard format is +/-DD MM SS.S - sign, degrees, arcminutes, arcseconds, separated by spaces. Alternatively, it may be entered as degrees (+/-DD.DDDDD), in which case it will be converted to sexagesimal during verification. If no sign is given it will be assumed to be positive.
Required.

** Is the observation (part of) a grid?

Logical value indicating whether this target is part of a grid of pointings. The default is 'N'. The observer is advised that there will be a reduction in the slew tax charged for a series of contiguous or nearly contiguous pointings each separated by no more than a degree from its nearest neighbor (a grid), provided that there is no instrument set-up or observing mode change. Proposers MUST prepare a detailed description of the grid positions (preferably a figure) to be sent to the CXC director (or his designate) upon request. Please refer to the CfP http://cxc.harvard.edu/proposer/CfP/ for details.

Grids may be entered as separate targets. Alternately, for a large number of pointings with identical observing parameters, you may specify all pointings by entering the grid center (the average coordinates of all grid pointings) in the R.A. and Dec fields above, and then also specifying the 3 general grid parameters below. This shortens and simplifies the proposal, but still allows target duplication checks and proper accounting of time and targets at peer review. Approved programs will be required to provide exact pointings within the grid to the CXC.

** Unique Grid name

A unique grid name allows the pointings in a grid to be more easily associated, scheduled, or searched as an ensemble in the CXC database. Required for all pointings intended to be part of a grid. Maximum of 30 characters.

** Number of grid pointings

The total number of grid pointings. Input of this datum indicates that the proposer wishes to use the parameterized generation of grid pointings for proposal purposes, rather than individual target pages. Default is blank. If grid parameters are used, the minimum value is 2.

** Distance from center to farthest grid pointing (degrees)

Distance in degrees between the center (average) grid coordinates entered in the R.A. and Dec fields above, and the intended pointing that is farthest from that center. Maximum value is numerically equal to the number of pointings.

** Offset Pointing (Y/Z Detector Target Offset )

The user may wish to offset-point the observatory pointing for a number of reasons, e.g., to reduce the effects of ACIS pile-up or to avoid HRC pore limits by blurring the image. Offset pointing is discussed in section 3.2 of the Proposer's Observatory Guide(POG) .

Most observers/proposers should leave BLANK all detector offsets in RPS if they wish their target to be close to the optical axis (best focus position). For either ACIS-I or ACIS-S, the unadjusted aimpoint (target position) falls 10 - 20 arcsec from the optical axis. To reduce this difference, a default offset will be added to every ACIS observation if both the ACIS Y- and Z- detector offsets are left blank in RPS.

A positive Z offset moves the target from ACIS-I towards ACIS-S. A positive Y offset moves the target from chip S3 towards chip S2. (see POG Figure 3.1). Note the 180 degree difference between the Y/Z coordinates and the Delta-Y/Delta-Z coordinates. Section 6.9 of the POG discusses the previous ACIS aimpoints and offsets in detail.

Note that the RA and Dec of the optical axis will depend upon the spacecraft roll angle at the time of the observation. If the observer wants the optical axis at a particular RA and Dec with a YZ target offset, then the observer must specify a roll constraint.

All units are arcmins. The overall valid range is -50.0 to +50.0 for (y,z) offsets. Thus it is possible to specify an offset so large that the target is not imaged anywhere on the detector, so exercise caution. Furthermore, if the target is offset by more than 15 arcmins, then ghost images (see POG Chapter 4) from the target may be visible.

Finally, offsets are implemented in software by redefining the pointing position. This means that roll constraints apply at the new position.

Y Pointing Offset:
Sense: negative Y offset moves the target away from the aimpoint in the direction of S4 on ACIS-S (ie. further onto the S3 chip)

Z Pointing Offset:
Sense: positive Z offset moves the target towards the readouts in ACIS-S (i.e. away from ACIS-I)

Recommendations: The default values (used if the field is left blank) are instrument dependent. Units are arcmin.

Default offsets for both ACIS-I and ACIS-S imaging, effective 19 Feb 2007, are 

         Y       Z
---------------------
 ACIS-S   0    -0.25
 ACIS-I  -0.2  -0.25
Any numeric value entered in the box will override the default values.

Proposers/observers who require specific offsets from the default aimpoint should enter into RPS Y,Z offsets in arcmin relative to the new aimpoint listed below. This is most likely to affect gratings observers who wish to optimize the position of chip gaps along the spectrum of their source. please refer to the webpage.

Position of the aimpoints with 0 offsets: 

        chipx   chipy
---------------------
ACIS-S   222     491
ACIS-I   942     991
Further details are available at http://cxc.harvard.edu/proposer/new_aimpoint.html

It is quite possible to specify an offset so large that the target is not imaged anywhere on the detector, so exercise caution. To make sure your target is placed as desired, we recommend use of the Observation Visualizer(ObsVis) available in the latest CIAO downloadable package at http://cxc.harvard.edu/ciao/download. Note that RPS software forbids entry of offsets larger than 10/30/20/50arcmin for ACIS-I/ACIS-S/HRC-I/HRC-S.

** SIM Translation Offset

Offset from nominal translation position. This is a motion of the SIM and thus the aimpoint away from the default position on the detector along the z-axis (which is along the axis from ACIS-S to ACIS-I).

Warning: The standard sub-arrays DO NOT take into account these recommended offsets. Thus if you wish to use a sub-array in conjunction with one of these offsets, you will need to specify it explicitly as a custom sub-array. For recommended values please see the web pages: http://cxc.harvard.edu/cal/Letg/ACIS_params for recommended offsets for LETG/ACIS-S gratings observations and http://space.mit.edu/ASC/calib/hetgsubarray.html for the HETG.

Units are in millimeters. 

Sense: a negative motion moves the aimpoint (and the target) towards the 
       readouts on ACIS-S (ie. away from ACIS-I)

Units: mm (scale 2.93mm/arcmin)

Default Values:

Configuration  Mode  SIM z(mm)  SIM z (arcmins)  SIM z (motor steps)*
----------------------------------------------------------------------------
HETG+ACIS-S     TE   -3         -1.02389         -1193
HETG+ACIS-S     CC   -4         -1.36519         -1591
LETG+ACIS-S     TE   -8         -2.73038         -3182
LETG+ACIS-S     CC   -8         -2.73038         -3182

Valid values by detector are: 

Detector   Minimum   Maximum
-----------------------------
HRC-S     -12.5439   61.3518
HRC-I     -61.3518   126.621
ACIS-S    -190.500   22.5685
ACIS-I    -22.5685   27.4739

** Do you want optical monitor data for your target?

Logical value indicating whether optical data from the aspect camera is requested for this observation. The default is 'N'.

The proposer should be aware that the aspect camera is NOT optimized for optical monitoring(the aspect camera is a 4-inch (10 cm) telescope that images the defocused beam onto an array of 3x3 pixels, each pixel is 5 arc sec on a side), however one can use the camera to measure the instrumental (~B+V+R) magnitude of target objects. If the target is fainter than ~10th mag, the aspect solution will be degraded by ~sqrt(4/5). Very roughly, at an instrumental magnitude of 12.5 one can do ~5% differential photometry in 10 seconds, and at 15.0 one can to 15% differential photometry in 200 seconds. Please see the Proposer's Observatory Guide for the limitations on the photometry and the expected signal-to-noise ratios (chapter on Aspect system).

The use of one of the guide-star channels as an optical monitor will be subject to peer review. The degradation of the aspect solution may lower the usefulness of the archive of the field. This will be weighed with the scientific value of the optical data.

** V Magnitude of Target

Specify the V magnitude of the target if the use of the optical monitor is desired. Valid range is -15.0 - 20.0. Required if optical monitor flag is set to "Y"

** Total Observing Time

The total exposure time in kiloseconds for requested observation(s) of this target. For monitoring observations or grids, this is the sum of all pointings. For example, for two observations of 40 kiloseconds each, specify 80 kiloseconds as the Total Observing Time and 2 for the Number of Observations in the 'Constraints' section.

Observations >160 ksec will have to be interrupted due to the satellite orbit. If the Uninterrupted Observation Required flag is checked, the pieces will be observed as contiguously as possible, and certainly in adjacent spacecraft orbits.

Valid range for an observing proposal is 1 - 10000 kiloseconds.

** Detector

Specifies which detector will be on the optical axis during the observation. The choices are: ACIS-S, ACIS-I, HRC-S or HRC-I. See the HRC and ACIS chapters of the Proposer's Observatory Guide for the aim point locations.

The target coordinates, including any specified offsets, will be placed at the aim point of the selected detector. Note a user should use the offset parameters (above) to move the target away from the nominal aim point should this be desired. 

Nominal aim points:
    ACIS-I:  aim point on chip I3
    ACIS-S:  aim point on chip S3, +.1667 arcmin Y offset
    HRC-I :  Detector center
    HRC-S :  1.3 arcmin from detector center to minimize effect of MCP
             boundaries

** Grating

Specifies which grating to use. Grating options are NONE, HETG, and LETG. The default is NONE which specifies no grating (direct imaging). You should use ACIS-S with the HETG and HRC-S with the LETG, unless you make a case otherwise in your proposal.

** Count Rate

The Count rate box must be filled in by all users. For detectors without gratings, this count rate is the source count rate in counts per second. For ACIS-S+grating or HRC-S+grating, this count rate is the zero-order count rate in counts per second. All count rates are to be specified as observed (not pile-up corrected).

For variable sources, supply the maximum expected count rate. This will allow for consistency checking of requested observation mode(s). The PIMMS tool can be used to calculate count rate.
Required.

** 1st Order Count Rate

The 1st order count rate entry should be filled in ONLY for those GOs who choose to use ACIS-S+grating or HRC-S+grating. The units are counts per second. All count rates are to be specified as observed (not pile-up corrected). Required for all observations that use gratings.

** Total Field Count Rate

This item requests the count rate across the field of the detector. This rate should include the total background (see the Proposer's Observatory Guide instrument chapters) as well as nearby sources. Units are counts per second. All count rates are to be specified as observed (not pile-up corrected).

** Is target an extended source ?

If the target is an extended source, set the flag to `Y'. The default is `N'.

** HRC Parameters

** HRC Timing Mode

Observers who wish to perform timing studies with the HRC should select this mode. This timing mode for HRC consists of using the HRC-S detector in what is called the Imaging Mode. In this mode, only the center segment of the HRC-S is active. The overall detector background is currently about 50 counts/sec (this is because of the overall background reduction associated with high solar activity reducing the Cosmic Ray flux). Sources with rates up to the telemetry limit (184 counts/sec) can be observed with no lost events and fully correct times. It is not advisable to look at very bright sources that actually come within about 10-15% of the telemetry limit to avoid the occasional statistical fluctuations that might cause the loss of some events. It is also not advisable to look at very strong point sources due to count rate limitations on the HRC (for HRC-S this is about 20-30 counts/sec).

* ACIS Parameters

This section contains the details for any observation which proposes to use the ACIS. ACIS has a large number of possible observing modes. The GO is urged to become familiar with each mode prior to specifying the details of the proposed observation.

* ACIS Required Parameters :

For faint sources (~< 0.01 cps), these are the only parameters that must be set.

** Exposure Mode

The exposure mode for ACIS for which two choices are possible: Timed Exposure (TE) or Continuous Clocking (CC). The default is TE. The CC mode may be used for bright, isolated sources to mitigate pileup. Please refer to the Proposer's Observatory Guide for more information.
WARNING! CC MODE WILL NOT RESULT IN AN IMAGE.

**Event Telemetry Format

Event Telemetry Format controls the packing of the data into the telemetry stream. This is similar to Bit Mode for ASCA. The default value is F(Faint).

Choice Format Exposure Mode Description
FFaintTE,CCreturns (x, y) position of event, energy, time-stamp + values of pixels in the 3x3 region surrounding event
VFVery FaintTEsame as above, except surrounding region is 5x5 pixels in size
GGradedTE,CCreturns (x, y) position of event, energy, time-stamp + Grade of pixels in 3x3 region

** CCDs On

                   I0  I1
                   I2  I3
            S0  S1 S2  S3  S4  S5
The ACIS CCD chip layout is as pictured. ACIS can read out a maximum of 6 chips. Each required chip should be set to 'Y'. If a chip is desirable, but the primary science could still be accomplished without it, please identify that chip as 'O' for Optional. Setting a chip selection to 'N' ensures that that CCD will not be used in any situation for the given observation. To maximize archival science, we recommend that you allow for the maximum number of chips possible to be turned on (i.e., set the total number of Yes+Optional chips as close to 6 as you can). Chandra operations nevertheless needs the option of turning off unnecessary chips to use less power on ACIS when thermal constraints dictate.

Values are:

In summary, 

 min 1, max 6 chips may be required, selected as 'Y'.   
 min 0, max 5 may be optional , selected as 'O#'.
 min 4, max 9 chips may be turned off, selected as 'N'.
A description of optional chips, including motivations and some recommended chip sets can be found on the Optional Chips webpage and in the ACIS chapter of the POG.

**I have reviewed the selection of ACIS chips and identified any chips whose operation is optional

Logical value indicating that you have reviewed your ACIS chip selection. This field is required if 5 or more chips have been selected and no optional chips have been identified.

*ACIS Optional Custom Parameters:

The custom parameters are available so users can mitigate the effects of pileup and avoid exceeding the telemetry saturation limit.

Parameters that affect PILEUP :

** Use most efficient frame exposure time?

Logical value indicating use of the most efficient values for the CCD Frame exposure time. If you do not wish to use the default most efficient values, please enter the exposure time in the CCD Frame exposure time field. 'Y' is required for CC exposure mode. The default is 'Y'.

** CCD Frame Exposure Time

The CCD frame exposure time is the fundamental unit for ACIS . It ranges from 0.0 to 10.0 seconds in 0.1 second increments. The default frame time is 3.2 seconds.

Responding with a `Y' to the question `Use most efficient frame exposure time?' allows the ACIS team to adjust the CCD frame time as necessary. The user may override that freedom by specifying a CCD frame time. Note that an entire CCD takes 3 seconds to read, so a 0.2 second frame time has a small observing efficiency which the proposer must justify. A shorter frame time can aid in mitigating pileup by a factor of up to 8. A shorter frame time is most easily achieved by the use of a Subarray.
Valid values: 0.0 to 10.0 seconds in 0.1 second increments depending on the number of active CCD's. The minimum times depend on the number of CCDs as follows: 

1 or 2 CCDs	- 0.1 second
3 or 4 CCDs	- 0.2 seconds
5 or 6 CCDs	- 0.3 seconds

** Subarray Type

Choices are: None, 1/2, 1/4, 1/8 and Custom

A subarray is a reduced region of all of the active(turned on) CCDs that will be read. A reduced region may also help to reduce the effects of pulse pile-up. The first box indicates whether the proposer intends to use the subarray capability.
Valid only for TE exposure mode. The default is 'None'.

PLEASE ENSURE THAT YOUR TARGET FALLS WITHIN THE CHOSEN SUBARRAY (e.g., use the Observation Visualizer(ObsVis) available in the latest CIAO downloadable package at http://cxc.harvard.edu/ciao/download)

Note that the minimum Frame Time depends on the size and location of the subarray. Read the ACIS chapter of the Proposer's Observatory Guide(POG) for more information.

The standard subarrays can be selected to avoid pileup approximately by the factor of the subarray size. The standard subarrays for ACIS-I use the values as listed in the table. For ACIS-S, the starting rows differ because of the different position of the aimpoint relative to the readout node. The ACIS chapter of the POG Guide contains a schematic of the locations of the default Subarrays. 

                     ACIS-I                       ACIS-S 
   Standard Size    Start Row     No. of Rows    Start Row  
   -------------------------------------------------------
       1/2            513            512           257 
       1/4            769            256           385 
       1/8            897            128           449

** Subarray: Start Row

The starting row that will be read for processing custom subarrays.
Valid range is 1 - 925.

** Subarray: No. Rows

The number of rows that will be read for processing custom subarrays. A minimum of 128 rows is required if multiple ACIS chips are selected. A minimum of 100 rows is required is a single ACIS chip is selected..
Valid range is 100 - 1024.

** Alternating Exposure Readout: Use Alternating Exposure Readout

Logical value indicating use of alternating exposure readout.
Valid only for TE exposure mode. The default is 'N'.

Alternating Exposure Readout observation sets the number of SECONDARY exposures that will follow each primary exposure. If n = 0, only primary exposures are used. A deadtime will result from the short exposure since the electronics still require 3.2 sec to process the full frame. Therefore, to minimize the deadtime, the number of short exposures should be kept to a minimum. The fraction of time during which data are taken is the ratio of the selected frame time to the sum of this and the nominal frametime: e.g. for a new frametime of n (<3.2) secs, the fraction of time during which data are taken is n/(3.2+n). Note the minimum on the primary exposure is 0.2 sec. Times longer than 3.2 seconds are discouraged until operational experience exists.

An example is useful. Suppose you want to sample the image in a repeated cycle of 4 exposures with a primary exposure time of 0.3 sec. If all 6 CCDs are active the secondary exposure time will be 3.2 sec. The resulting sequence of exposures will be 0.3 sec, 3.2 sec, 3.2 sec, 3.2 sec, 0.3 sec, 3.2 sec,. etc. until the total requested observing time is used.

** Alternating Exposure Readout: Number of Secondary Exposures

The number of secondary exposures that will follow each primary exposure. If n = 0, only primary exposures are used. Read the ACIS chapter of the Proposer's Observatory Guide for an estimate of the efficiency.
Valid range is 0 - 15.

** Alternating Exposure Readout: Exposure Time for Primary Cycle

The primary exposure time in tenths of seconds. The recommended time for a non-zero number of secondary exposures is 0.3. 
Valid times:        n=0 :  T-p = 3.2 sec
             non-zero n :  T-p = 0.2 - 10.0 sec

Parameters that affect TELEMETRY :

Before event candidates are written to telemetry, they are subjected to three sets of filters, each of which can cause them to be rejected. The filters can reject events by their grade code*, by their energy, and by their spatial location on the CCD array. The order in which these filters are applied is unimportant.

* At the present time, the proposer cannot change the set of grade codes to be rejected by the on-board grade filter; they were chosen to exclude only those event candidates that are almost certainly not caused by target X-rays. This is discussed in the Non-X-ray Background section of the Chandra Proposer's Guide.)

** Energy Filter: Use Energy Filter

All event candidates from all CCDs are filtered by energy before they are packed into the telemetry stream. This does not affect pulse pileup: it only reduces the telemetry. When this field contains 'N', the filter rejects only those events with energies below 0.08 keV or above 15.0 keV. When the field contains 'Y', the proposer gets to specify more restrictive values of Lower Energy Threshold and Energy Filter Range. (Note: additional energy filtering may be applied to events that fall within particular spatial windows, as described below. Such events will be rejected if they fail either filter.)

** Energy Filter: Lower Energy Threshold

Event candidates will be rejected if their energy lies below this value.
Units are keV; the valid range is 0.08 - 15.0 keV.
ACIS is insensitive to X-rays below this energy.

** Energy Filter: Energy Filter Range

Event candidates will be rejected if their energy lies above (Lower Energy Threshold + Energy Filter Range).
Units are keV; the valid range is 0.1 - 15.0 keV.
The effective area of the Chandra mirrors above 10 keV is essentially zero, but X-ray pileup can result in event candidates with energies above 10 keV.

** Use Spatial Windows?

By setting this field to 'Y', the user can specify one or more spatial window filters -- rectangular regions on specific chips -- within which event candidates can be rejected according to their energy or to their frequency of occurrence. The use of spatial windows does not affect the way the CCD is read out, so there will be no impact on event pile-up. Spatial windows will reduce the telemetry volume by removing event candidates.

As many as six spatial windows may be specified for each chip. If windows overlap, the order in which they are defined in the RPS form is important: for each event candidate centered at (CHIPX=x, CHIPY=y), the on-board software examines all spatial windows defined for that chip, in the order specified in the RPS form, lowest index first, and decides whether to reject the event based on the parameters in the first window that contains that (x,y). If the event lies outside all windows, it will not be rejected by the window filter.

If more than 3 spatial windows are desired, use the Additional Spatial Windows text field to define their parameters.

BE SURE TO CHECK THAT YOUR TARGET FALLS WITHIN THE CHOSEN WINDOWS (Hint: use ObsVis, the Observation Visualizer, distributed with the CIAO package from "http://cxc.harvard.edu/ciao/download/".

Example:

Three rectangular areas are defined on the S3 chip: window #1 accepts all events that fall within its bounds with energies from 0.1 to 10.0 keV; window #2 accepts one out of two events within its bounds, provided they are not within the overlap with window #1 and provided they are in the energy range 0.3 to 10.0 keV; the third window covers the entire CCD and rejects all events that are not within the areas covered by the other windows.

Window
Order		 Chip
ID		 Sampling
Frequency		 Starting
Column		 Column
Width		 Starting
Row		 Row
Height		 Lower Energy
Threshold		 Energy
Range
1 S3 1 200 500 400 500 0.1 9.9
2 S3 2 500 400 200 400 0.3 9.7
3 S3 0 1 1024 1 1024

1024










Window 1







Window 2


Window 3



S3
CHIPY
0

0          CHIPX 1024

** Spatial Window: Order

The index of this spatial window: if a chip's spatial windows overlap, the window with the lowest index determines how events falling within the overlap region are to be filtered. Valid values are: 1-36.

** Spatial Window: Chip

The ACIS chip on which this spatial window is defined.
Valid values are: I0,I1,I2,I3,S0,S1,S2,S3,S4,S5.
This parameter is required for all spatial windows.

** Spatial Window: Sample Rate

It determines what fraction of the events are to be accepted* by the spatial window filter, i.e.,

0 All of the events falling within the window are rejected.
1 All of the events falling within the window are accepted, provided they meet the energy threshold and range criteria*.
n Every nth event falling within the window is accepted, provided it meets the energy threshold and range criteria*; the remainder are rejected.

*  acceptance by the spatial window filter is no guarantee that the event will be output to the telemetry stream -- it may be rejected by the grade filter or the overall energy filter.

This parameter is required for all spatial windows.
Valid values are 0-255.

Examples:

  1. Accept every third event in a 100-row band centered near the suggested aimpoint of the S3 chip (CHIPX=215, CHIPY=497), discarding all other S3 events.

    Window
    Order    		 Chip
    ID    		 Sampling
    Frequency    		 Starting
    Column    		 Column
    Width    		 Starting
    Row    		 Row
    Height    		 Lower Energy
    Threshold    		 Energy
    Range
    1 S3 3 1 1024 447 100

    2 S3 0 1 1024 1 1024

    Note that this operation required two windows for the S3 chip: the first to accept one-in-every-three events falling within the band, the second to reject all events outside the band. Since neither "Lower Energy Threshold" nor "Energy Range" was defined for either window, they default to 0.08 keV and 15.0 keV, respectively, unless 'Y' was selected for Energy Filter: Use Energy Filter, in which case, the Energy Filter: Lower Energy Threshold and Energy Filter: Energy Filter Range values will be used.

  2. Accept every fifth event with energy less than 10keV falling within a 100-by-100 pixel square centered on the zeroth order aimpoint in a grating observation; retain all events falling outside that area.

    Window
    Order    		 Chip
    ID    		 Sampling
    Frequency    		 Starting
    Column    		 Column
    Width    		 Starting
    Row    		 Row
    Height    		 Lower Energy
    Threshold    		 Energy
    Range
    1 S3 5 226 100 447 100 0.1 9.9

    Note that this operation required only one S3 window since the filter will not reject any event falling outside the defined window area(s).

** Spatial Window: Start Column

The first column of the rectangular area that is to be filtered.
This parameter is required for all spatial windows.
The valid range is 1 - 1023.

** Spatial Window: Width of Window

The number of columns in the rectangular area that is to be filtered.
This parameter is required for all spatial windows.
The valid range is 1 - 1024.

** Spatial Window: Start Row

The first row of the rectangular area that is to be filtered.
This parameter is required for all spatial windows in TE mode. In CC-mode, it will be ignored.
The valid range is 1 - 1023.

** Spatial Window: Height of Window

The number of rows in the rectangular area that is to be filtered.
This parameter is required for all spatial windows in TE mode. In CC-mode, it will be ignored.
The valid range is 1 - 1024.

** Spatial Window: Lower Energy Threshold

Discard all events within this window whose energies are less than this value. The units are keV.
The valid range of this parameter is 0.08 - 15.0 keV.
If omitted, the value will depend on the choice of Use Energy Filter in the preceding section. If 'Y', its Energy Filter: Lower Energy Threshold value will be used for the window; otherwise, the window's Lower Energy Threshold value will default to 0.08 keV.

** Spatial Window: Energy Range

The range of event energies to be accepted, i.e., events with energies above (Lower Energy Threshold + Energy Range) will be rejected. The units are keV.
The valid range of this parameter is 0.1 - 15.0 keV.
If omitted, the value will depend on the choice of Use Energy Filter in the preceding section. If 'Y', its Energy Filter: Energy Filter Range value will be used for the window; otherwise, the window's Energy Range value will default to 15.0 keV. Note that the effective area of the mirrors above 10 keV is essentially zero, but pileup can cause multiple photons of lower energy to register as single events with energies above 10 keV.

** Additional Spatial Window definitions

Additional spatial window filters may be defined in this text box, one per line, using the same (comma-delimited) fields as in the table structure, viz., window order (4-36), chip ID (I0-S5), sampling frequency (0-255), starting column and width, starting row and height, lower energy threshold (0.08-15.0 keV), and energy range (0.1-15.0 keV). If your proposal is approved, the CXC will enter this additional data in the Observation Catalog. Up to 6 windows may be specified for each chip, for a total of no more than 36 spatial windows.
This field is limited to a maximum of 800 characters, including commas and line feeds.

* CONSTRAINTS

This section contains the details for any time critical observation. The constraints may be required (Y) or preferred (P). If any constraint is required, the observation is considered time constrained and will be subject to the limits set for constrained observations. If the constraints are only preferred, the flag should be set to 'P'. The CXC will interact with the PI/observer to see if the 'Preferred' requests can be met, but they are NOT GUARANTEED.

The types of constraint are: 

Window:		        In a fixed time-window
Roll:                   Roll constrained 
Phase dependent:	Samples at a given phase
Monitoring: 		Repeated observations of a single target at specified intervals. (DDTs only)
Grouping: 		Single or multiple targets observed in any order and encompassed by a single time interval. (DDTs only)

Uninterrupted:          Absolutely no interruptions
Coordinated Obs.:       Coordination with other observatories/telescopes
'Monitoring' and 'Grouping' observations are mutually exclusive. These two options are not available to the observations that were already approved at the Peer Review. If you have any changes to the monitoring or grouping parameters that were approved at the Peer Review, please contact your uplink support scientist.

** Is this a constrained observation?

This entry is automatically filled in by RPS based on the flags set for the constraint parameters: Window, Roll, Phase Dependent, Monitoring, Grouping, Uninterrupted and Coordinated Observation.

** Window Constraints

These parameters indicate the earliest observation start time and the latest observation end time. USE THE LARGEST VIABLE WINDOW. Do not enter window constraints merely to indicate periods of sunblock, as these are accounted for by Chandra Mission Planning.

The start and end times must be given in UT . Up to 4 window constraints may be entered per observation. See the Call for Proposals document for the anticipated dates covered by this cycle. The window start/stop format is dd-mon-yyyy hh:mm where : 

    dd = day of month
   mon = 3 character abbreviation of month. Valid Values:
         Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec
  yyyy = full year (ie: 2002)
    hh = hours (valid values 0-23)
    mm = minutes (valid values 0-59)

** Window Constraint?

Logical value indicating a window constraint exists for this observation.
Options are: Y (Yes, required), P (Preferred), N (No). The default is 'N'.

** Window Constraint: Start

The time in UT specifying the earliest observation start time. Format is dd-mon-yyyy hh:mm.
Required if Window Constraint? is 'Y' or 'P'.

** Window Constraint: Stop

The time in UT specifying the latest observation end time. Format is dd-mon-yyyy hh:mm.
Required if Window Constraint? is 'Y' or 'P'.

** Roll Constraints

The spacecraft roll is the angle between celestial north and the spacecraft -Z (minus Z) axis projected on the sky, as measured from N through W. The roll angle is constrained as a function of time for thermal control and because power must be supplied by the solar cells. For any given time and target, there is a nominal roll angle for which the solar power arrays are aimed directly at the sun. The nominal roll for a target may be displayed using the Observation Visualizer(ObsVis) available on the web at http://obsvis.harvard.edu/ or in the latest CIAO downloadable package at http://cxc.harvard.edu/ciao/download.

A roll constraint translates directly into a constraint on the day and time when an observation may be carried out. It should only be specified for cases in which a specific attitude is required to meet scientific objectives. The tool, ObsVis, provides a display of roll angle as a function of time for a given target.

A maximum of 4 roll constraints may be entered.

** Roll Constraint?

Value indicating a roll constraint exists for this observation.
Options are: Y (Yes, required), P (Preferred), N (No). The default is 'N'.

** Roll Angle and Roll Tolerance

The spacecraft roll angle and roll tolerance(defined as the half-range and assumed symmetric) for the observation. Valid range is 0.0 - 360.
Required if Roll Constraint? is 'Y' or 'P'.

** Is 180 Rotation OK?

Logical value indicating whether a 180 degree rotation of the roll angle is acceptable. The default is 'N'.

** Phase Dependent Observation

Value indicating that the observation is to be spread over a number of intervals with a fixed interval between them and a given reference date. The Epoch is the reference date given in MJD and the Period is the interval in days. The Minimum and Maximum Phase are the minimum and maximum orbital phase.
Options are: Y (Yes, required), P (Preferred), N (No). The default is 'N'.

** Phase Dependent: Epoch (MJD)

For Phase Dependent observations, the reference date (MJD). The observations will be made at an integral number of Periods from this date. The reference date must be within 5 years of the current date.
Required if Phase Dependent Observation? is 'Y' or 'P'.

** Phase Dependent: Period (days)

The period in days between phase dependant observations.
Required if Phase Dependent Observation? is 'Y' or 'P'.

** Phase Dependent: Minimum Phase

Minimum orbital phase to be observed. Values must be between 0 and 1.
Required if Phase Dependent Observation? is 'Y' or 'P'.

** Phase Dependent: Minimum Phase Error

The error on the minimum orbital phase. This parameter sets how precisely the phase range will be covered. Values must be between 0 and 0.5.
Required if Phase Dependent Observation? is 'Y' or 'P'.

** Phase Dependent: Maximum Phase

Maximum orbital phase to be observed. Values must be between 0 and 1.
Required if Phase Dependent Observation? is 'Y' or 'P'.

** Phase Dependent: Maximum Phase Error

The error on the maximum orbital phase. This parameter sets how precisely the phase range will be covered. Values must be between 0 and 0.5.
Required if Phase Dependent Observation? is 'Y' or 'P'.

** Monitoring Observation

Logical value indicating whether the observation is to be made in several parts at fixed intervals but with no fixed starting time. The number of parts is specified in the "Number of Observations" field. The default is 'N'.

** Monitoring Observation: Number of Observations

Number of observations of the target. For monitoring observations , enter the number of parts into which the total exposure time will be divided. The default is a single observation of the target.

** Geometric Factor for Monitoring Observations

Enter the geometric factor to be used for this monitoring observation. For linear progression, the geometric factor should be set to 1. The default is 1.
Required if Monitoring Observation? is 'Y'.

For example: 

                Number of Observations:  4
                Geometric Factor:  3.0
                Interval (days) : 10.0 
                Tolerance(%)    : 10.0   (percent)
The observation would be split into 4 observations. The Tolerance is +/- 1 day (0.10 * specified interval of 10 days). For a Geometric Factor of 3.0, the initial observation would be scheduled and then the 3 remaining observations scheduled within 9-11 days after the initial observation, 27-33 days after the 1st followup, and 81-99 days after the second followup observation. If the Geometric Factor was set to 1.0, the 3 remaining observations would be scheduled within 9-11, 19-21, and 29-31 days after the initial observation.

** Interval Between Monitoring Observations

Interval between monitoring observations in days. Valid range is 0.0 - 364.0 days.
Required if Monitoring Observation? is 'Y'.

** Interval Tolerance for Monitoring Observations

Interval tolerance for monitoring observations. Unit is percentage(%) of the requested monitoring interval. Valid range is 0 - 100.
Required if Monitoring Observation? is 'Y'.

** Group Observation

Logical value indicating whether the observation needs to be observed within a relative time range with other targets in this proposal. The default is 'N'.

** Group Identification

Enter the group identification (e.g. short name selected by the observer) to be used to identify which targets in this proposal need to be grouped within a relative time range. Maximum of 10 characters.
Required if Group Observation? is 'Y'.

** Interval for Grouping Observations

Relative Time Interval for grouping observations. Valid range is 0.0 - 364.0 days.
Required if Group Observation? is 'Y'.

** Uninterrupted or Contiguous Observation Required

Value indicating that the science can only be optimized if the observation is interrupted as little as possible. Use sparingly, as this WILL BE COUNTED AS A CONSTRAINT. This flag should, in general, NOT be used unless the requested Observing Time is >20 ksec. The typical operating mode for Chandra generally results in the allocated observing time being assigned to a single pointing.

Options are: Y (Yes, required), P (Preferred), N (No). The default is 'N'.

'Y' indicates that the science goals can only be achieved if the observation is not interrupted. Use 'Y' sparingly, as this WILL BE COUNTED AS A CONSTRAINT.

Use 'P' if the science goals do not require - but will clearly be optimized by - minimized interruptions. As a preference, this will be implemented to the extent allowed by all other demands on the scheduling process.

Note that for short observations, normal Chandra scheduling results in the allocated observing time being assigned to a single pointing, but there is no guarantee of this for any exposure time above about 20 ksec.

Observations >160 ksec will have to be interrupted due to the satellite orbit. If the uninterrupted flag is checked, the observations are constrained such that the pieces will be observed as contiguously as possible, and certainly in adjacent spacecraft orbits.

** Must this observation be coordinated with that of another space-based observatory?

Value indicating that the Chandra observations are to be coordinated with another space-based or the VLA observatory. Ground-based observations other than the VLA are not available as a constraint (Preference only).
No default value. If set to Yes, required, the observation WILL BE COUNTED AS A CONSTRAINT and is subject to the limits set for the number of approved constrained observations during the Chandra Peer Review.

Options:
WWWE-mailDescription
No constraintNNo coordination needed
Yes, required Y Coordination required
PreferredPCoordination helpful but not required

** Maximum Time Interval Encompassing Coordinated Observations

Relative Time Interval for coordinated observations. Valid range is 0.0 - 364.0 days. Required if Coordinated Observation? is 'Yes, Required' or Preferred. This is the maximum scientifically-permitted interval encompassing the Chandra observation and those of the coordinating observatory(ies). If the intervals differ for different coordinating observatories, provide details in the Remarks field and check "Are there additional constraints or preferences in the remarks?"

** Observatories

If 'Y' or 'P' is selected in the 'Must this observation be coordinated with that of another space-based observatory? ' field, specify the other space based observatories or VLA. For other ground-based observatories, just use 'Ground'. Except for VLA, ground-based observations are not available as a required constraint (Preference only).

Choices are: HST, RXTE, XMM, Spitzer, VLA, Ground.
Maximum of 60 characters.

** Are there additional constraints or preferences in the remarks?

Value indicating there are additional observational constraints or preferences described in the Remarks field. No default value. If set to Y, the observation is subject to the limits set for the number of approved constrained observations during the Chandra Peer Review. Required instrument configurations are not considered to be observing constraints.

Options are: Y (Yes, required), P (Preferred), N (No).

** Remarks

Enter any additional target remarks in this field. Remember that constraints should be entered into the appropriate Constraint fields on this form. Only those constraints that cannot be specified using the existing constraint fields should be entered in this 'Remarks' field.
Maximum of 600 characters.

* TOO Details

This section contains the additional details for Targets of Opportunity (TOO).

** Is this the trigger target for a TOO?

If this target is the trigger target (first observation) for a TOO, please set the value to Yes. If this target defines a different instrument configuration/offset for a TOO followup observation, please set the value to No.

** TOO Response Type

Select the response time bin for the TOO. This is the response time that will be required of the Chandra personnel when the TOO is triggered. For required response times which cross a boundary between the defined categories, the observer should select the slower category consistent with the requirements.
Unit is days. Options are: 0-4, 4-12, 12-30, >30.
Required for all trigger targets for TOOs.

** Probability of TOO occurring

Enter the probability of the TOO occurring during the proposed Chandra cycle. The default is 1.0. Valid values are 0.1 - 1.0.

** Exact CXC start/stop response window

Start time is the minimum time after the official request to trigger the Chandra TOO observation that the exposure should begin. Stop time is the maximum time after that trigger for the exposure to begin and still be scientifically useful. Units are days. These times may cross boundaries with the selected 'TOO Response Type'. Required for all trigger targets for TOOs.

** Exact TOO Trigger Criteria

Specify the trigger criteria for the TOO, e.g. information that will establish the trigger,such as how bright the source should be, in which instrument or telescope, minimum time above threshold brightness, etc..
Maximum of 400 characters. Required for all trigger targets for TOOs.

** Followup Observations

If followup TOO observations are being proposed, please enter the exposure time, delay (time interval), tolerance,and target number for each followup in the Followup Summary table. All followups must be specified in the Followup Summary table, but the table should NOT include the trigger observation. Target Number MUST be specified for every followup.

Note that the Trigger target should be labelled as such (Is this the trigger target for a TOO? set to 'Y') and that the exposure time for the trigger target should be the full observing time for the trigger and all followup observations.

If a different instrument configuration or offset is required for a followup, you must enter that observation as a new target with all observational parameters specified, setting the 'Total Observing Time' to 0 and 'Is this the trigger target for a TOO?' to 'N'(No). For non-trigger target forms, all other fields in the TOO Details section must be blank. Be sure to enter the correct target number for each followup observation in the Followup Summary table of the trigger observation. Target Number MUST be specified for every followup.

For a detailed example of how to use the RPS TOO Followup forms, see http://cxc.harvard.edu/proposer/threads/TOO.

Note: Followup fields are not available to the observations that were already approved at the Peer Review. If you have any changes to the followup parameters that were approved at the Peer Review, please contact your uplink support scientist.

** Followups: Observing Time

Enter the requested duration for this TOO followup observation in kiloseconds.
Required for TOO followup observations.

** Followups: Time Interval(days)

Enter the desired time interval in days between this observation and the preceding observation.
Required for TOO followup observations.

** Followups: Tolerance (%)

Enter the interval tolerance for this TOO observation. Unit is percentage(%) of the requested time interval. Valid range is 0 - 100.
Required for TOO followup observations.

** Followups: Target Number

Please enter the target number in this proposal which defines the instrument configuration for this followup target.
Required for TOO followup observations.

** If followups, time allocated for initial TOO

Enter the amount of the total observation time that should be used for the initial TOO observation. The remaining time will be used for the followup observations.
Required if 'Number of followup observations' is greater than 0.

** TOO followup instructions

Specify additional TOO followup instructions only if the 'Number of followup observations' is greater than 0.
Maximum of 1500 characters.

**TOO Coordinated Observations:

Indicate all of the coordinated observations (simultaneous or contemporaneous) associated with this TOO in the appropriate box for coordination with other space-based observatories. This includes observations already approved under other programs, even if time is not requested as part of this proposal. Coordinated observations included only in proposal text will not be recognized or accepted. For non-Chandra observations approved after your Chandra proposal has been accepted, you may request coordination if and when you trigger your TOO. Any such request for additional coordination or observing constraints must be made to the Director and approved by the Chandra Director's Office. For a constraint approved in this way, the CXC will try to accommodate on a best efforts basis.




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Last modified: 05/16/07