Accepted Cycle 16 Observing Proposals

SN SNR AND ISOLATED NS

Proposal Number	Subject Category	PI Name	Type	Time (ks)	Title
16500009	SN, SNR AND ISOLATED NS	Sasaki	GO	50	The possible PWN candidate in the LMC SNR [HP99] 456
16500090	SN, SNR AND ISOLATED NS	Berger	TOO	20	Rapid Observations of Short-Duration Gamma-Ray Bursts: Accurate Positions Hold the Key to the Progenitor Population
16500118	SN, SNR AND ISOLATED NS	Burrows	GO	140	CHANDRA CYCLE 16 SPATIAL AND SPECTRAL MONITORING OF SN 1987A
16500129	SN, SNR AND ISOLATED NS	Reynolds	GO	50	G141.2+5.0: An Unusual New Pulsar-Wind Nebula
16500168	SN, SNR AND ISOLATED NS	MEREGHETTI	GO	50	High angular resolution study of the mode-switching PSR B0943+10
16500197	SN, SNR AND ISOLATED NS	Slane	GO	100	Changes in Latitude: A Chandra Study of G296.5+10.0
16500286	SN, SNR AND ISOLATED NS	Halpern	GO	40	The Energetic Magnetar in HESS J1713-381/CTB 37B
16500341	SN, SNR AND ISOLATED NS	Tiengo	TOO	70	Measuring magnetar distance from the dust echo of a bright burst
16500362	SN, SNR AND ISOLATED NS	Klochkov	GO	90	Revealing the nature of the Central Compact Object candidate CXOU J181852.0-150213
16500414	SN, SNR AND ISOLATED NS	Miceli	GO	10	Investigating the nature of AX J1714.1-3912
16500418	SN, SNR AND ISOLATED NS	Margutti	TOO	50	Mapping the Zoo of engine driven explosions with late-time X-rays
16500454	SN, SNR AND ISOLATED NS	Kamitsukasa	GO	30	Revisiting Vela shrapnel D: Understanding the dynamics of the SNR ejecta interaction with an interstellar cloud
16500486	SN, SNR AND ISOLATED NS	Gotthelf	GO	160	HESS~J1640-465: Powering the most luminous gamma-ray source in the Galaxy
16500511	SN, SNR AND ISOLATED NS	Kaspi	TOO	1680	Target-of-Opportunity Chandra Observations of Glitching High-B Radio Pulsars: Searching for Magnetar Metamorphoses
16500533	SN, SNR AND ISOLATED NS	Reynolds	GO	20	CHARACTERIZING A NEW RADIO FAINT SNR: G309.4-0.1
16500534	SN, SNR AND ISOLATED NS	Margutti	TOO	10	Energetics and Environment of Hydrogen-poor Core-Collapse SNe
16500556	SN, SNR AND ISOLATED NS	Pavlov	GO	130	The puzzling dynamic nebula powered by the pulsar B1259-63 in a high-mass binary
16500634	SN, SNR AND ISOLATED NS	Rangelov	GO	50	Snap-shot survey of unidentified Fermi sources
16500640	SN, SNR AND ISOLATED NS	Rea	TOO	2465	PROMPT STUDY OF MAGNETAR OUTBURSTS WITH CHANDRA
16500642	SN, SNR AND ISOLATED NS	Pires	GO	20	A possible near-infrared counterpart for the isolated neutron star in the Carina Nebula
16500703	SN, SNR AND ISOLATED NS	Posselt	GO	78	The cooling of the Cas A CCO: fast or slow?
16500705	SN, SNR AND ISOLATED NS	Borkowski	LP	400	Nonuniform expansion and brightening of the youngest Galactic SNR G1.9+0.3
16500718	SN, SNR AND ISOLATED NS	Borkowski	GO	100	Expansion of Kes 73, a shell supernova remnant containing a magnetar
16500720	SN, SNR AND ISOLATED NS	Troja	TOO	50	IDENTIFY THE SIGNATURE OF NEUTRON STAR MERGERS THROUGH RAPID CHANDRA/HUBBLE OBSERVATIONS OF A SHORT GRB
16500739	SN, SNR AND ISOLATED NS	Yamaguchi	GO	70	(Re-)Constraining the Cosmic-Ray Acceleration Efficiency and Magnetic Field Strength in the Northeast Rims of RCW 86
16500768	SN, SNR AND ISOLATED NS	Posselt	GO	35	The proper motion of the isolated neutron star RXJ0806.4-4123
16500812	SN, SNR AND ISOLATED NS	Pannuti	GO	50	New Chandra Observations of the Archetypical Mixed-Morphology Galactic Supernova Remnant W28 (G6.4-0.1)
16500832	SN, SNR AND ISOLATED NS	Kargaltsev	GO	120	X-RAY COUNTERPARTS OF PUZZLING GEV-TEV SOURCES
16500844	SN, SNR AND ISOLATED NS	Marelli	GO	130	Deep study on the proper motion and collimated tail of the oldish PSR J2055+2539
16500869	SN, SNR AND ISOLATED NS	Fruchter	TOO	120	The Astrophysics of the Most Energetic Gamma-Ray Bursts
16500912	SN, SNR AND ISOLATED NS	Fruchter	GO	120	The Burst of the Century

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500009

Title: The possible PWN candidate in the LMC SNR [HP99] 456

Type: GO Total Time (ks): 50

PI Name: Manami Sasaki

Abstract: The Large Magellanic Cloud (LMC) offers the ideal laboratory for the study of a large sample of supernova remnants (SNRs). The source [HP99] 456 was one of the promising SNR candidates discovered in the ROSAT survey of the LMC. A new observation of this source with XMM-Newton revealed a complex morphology, composed of a thermal circular shell and a non-thermal hard emission. X-ray and radio data suggest the identification of the hard source as a pulsar wind nebula (PWN), with a peculiar morphology in X-rays. Higher spatial resolution is required to resolve the hard X-ray emission and determine the correct radio counterpart. We therefore propose a high-resolution observation of the hard source with Chandra ACIS-S.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+05:41:38.90	-66:58:48.00	[HP99] 456	ACIS-S	None	50.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500090

Title: Rapid Observations of Short-Duration Gamma-Ray Bursts: Accurate Positions Hold the Key to the Progenitor Population

Type: TOO Total Time (ks): 20

PI Name: Edo Berger

Abstract: Only 1/4 of all short GRBs are localized to sub-arcsecond accuracy, required for unambiguous host and redshift identifications, determination of the burst environment (disk, bulge, halo, IGM), and assessment of natal kicks. These properties determine the identity and ages of the progenitors, and the GRB explosion physics. Thus, much of our knowledge depends on a handful of events, which are moreover biased to high density environments by virtue of optical/radio detections. Here we propose to double the fraction of events with sub-arcsecond positions, and overcome the density bias, using rapid Chandra observations of bursts with only Swift/XRT positions. Swift data will guarantee Chandra detections at <4 days, and follow-up work will delineate the burst/host properties.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
		Short-GRB-Astrometry-1	ACIS-S	None	20.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500118

Title: CHANDRA CYCLE 16 SPATIAL AND SPECTRAL MONITORING OF SN 1987A

Type: GO Total Time (ks): 140

PI Name: David Burrows

Abstract: Regular monitoring of SN 1987A, the only supernova remnant in which we can study the early developmental stages in detail, is critical to testing models of remnant evolution, nonequilibrium ionization processes, thin plasma spectra, and physical processes in dusty plasmas. SN 1987A presents a unique opportunity to observe the birth and early evolution of a supernova remnant at high spatial and spectral resolution for the first time. We propose to continue our program of monitoring SN 1987A at roughly six month intervals in Cycle 16.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+05:35:28.00	-69:16:11.10	SN 1987A	ACIS-S	HETG	70.0
+05:35:28.00	-69:16:11.10	SN 1987A	HRC-S	LETG	70.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500129

Title: G141.2+5.0: An Unusual New Pulsar-Wind Nebula

Type: GO Total Time (ks): 50

PI Name: Stephen Reynolds

Abstract: Pulsar-wind nebulae (PWNe) showcase the winds emitted by pulsars and the processes by which particles are accelerated in relativistic shock waves. Many older PWNe have been discovered recently in gamma rays, but a persistent puzzle, pointing to our fundamental lack of understanding of particle energization in PWNe, concerns the relation of radio emission to X and gamma-ray emission. We propose to observe a recently discovered radio PWN, the first such in 17 years, which has a steep radio spectrum but otherwise the standard properties of radio PWNe. We plan to search for a point source; characterize any X-ray nebula; and compare G141.2+5.0 to the small group of steep-spectrum radio PWNe to try to elucidate the radio-to-X-ray connection in PWNe in general.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+03:37:15.00	-61:52:60.00	G141.2+5.0	ACIS-S	None	50.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500168

Title: High angular resolution study of the mode-switching PSR B0943+10

Type: GO Total Time (ks): 50

PI Name: SANDRO MEREGHETTI

Abstract: Recent observations unvealed a remarkable and unique behaviour in the X-ray emission of the mode-switching radio pulsar PSR B0943+10. Its X-ray flux varies in correlation with the mode of radio emission and the spectrum requires the combination of thermal and non-thermal components with different variability properties. Part of the observed X-ray emission could originate from a pulsar wind nebula, but no high angular resolution observations of this pulsar have been obtained so far. Assessing the presence of diffuse emission with Chandra is essential in order to correctly disentangle the X-ray emission components of PSR B0943+10 and to understand how they relate with changes in the magnetosphere geometry and with the different modes of its pulsed radio emission.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+09:46:07.70	+09:52:00.80	PSR B0943+10	ACIS-S	None	50.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500197

Title: Changes in Latitude: A Chandra Study of G296.5+10.0

Type: GO Total Time (ks): 100

PI Name: Patrick Slane

Abstract: G296.5+10.0 is a supernova remnant at high Galactic latitude, with a distinctive bilateral morphology. Faraday rotation measurements provide evidence for a toroidal magnetic field component that may have been produced in a magnetic wind from the progenitor star. Gamma-ray observations indicate that the remnant has been an efficient particle accelerator. We propose Chandra observations of the remnant to search for evidence of the expected wind composition and density profile, and to determine the nature and spatial distribution of a hard spectral component. We will also investigate an apparent interaction with a small molecular cloud and search for X-ray emission corresponding to observed filamentary structure in the radio.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+12:12:02.00	-52:42:37.00	G296.5+10.0 - SE	ACIS-I	None	40.0
+12:07:13.00	-52:52:12.00	G296.5+10.0 - SW	ACIS-I	None	60.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500286

Title: The Energetic Magnetar in HESS J1713-381/CTB 37B

Type: GO Total Time (ks): 40

PI Name: Jules Halpern

Abstract: The spin-down power of the 3.82 s AXP in the SNR CTB 37B is among the largest of magnetars, and it may be the youngest one as well. We propose to continue to monitor its spin-down rate, which varies by a factor of 2. Magnetars with the largest spin-down power are SGRs, and a marked increase in their spin-down torque often precedes an outburst. In this regard, CXOU J171405.7-381031 is very similar to SGR/AXP 1E 1547.0-5408, the magnetar with the largest spin-down power. By analogy with 1E 1547.0-5408, we may be observing the behavior of an SGR before its outburst. The pulse profiles show a change in shape above 8 keV, which suggests that a separate high-energy spectral component is present. We will examine the high-energy spectrum and pulse with NuSTAR.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+17:14:05.70	-38:10:30.90	CXOU J171405.7-381031	ACIS-S	None	20.0
+17:14:05.70	-38:10:30.90	CXOU J171405.7-381031	ACIS-S	None	20.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500341

Title: Measuring magnetar distance from the dust echo of a bright burst

Type: TOO Total Time (ks): 70

PI Name: Andrea Tiengo

Abstract: In 2009 we discovered, around the magnetar 1E1547.0-5408, 3 bright X-ray expanding rings due to scattering of the radiation of a strong burst by 3 dust layers in our Galaxy. We propose rapid follow-up observations with Chandra in the case that a similar phenomenon will occur again in a magnetar. This would provide the first high resolution two-dimensional images of an X-ray expanding ring around an astrophysical object and constrain the source distance and energetics of the emission producing the dust echo. Moreover, the time evolution of the ring intensity and spectrum, depending on the dust grains composition and size, is a powerful tool to test the different interstellar dust models. Previous versions of this proposal were accepted (but never triggered) in Cycle 12, 13, 14, and 15.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
		Magnetar scattering halo	ACIS-I	None	70.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500362

Title: Revealing the nature of the Central Compact Object candidate CXOU J181852.0-150213

Type: GO Total Time (ks): 90

PI Name: Dmitry Klochkov

Abstract: Central Compact Objects (CCOs) are low-magnetized cooling NSs. CCOs potentially provide an "undisturbed" view of the NS surface emission giving an access to their mass and radius. Despite their importance, only a dozen of CCOs are known. Thus, any addition to this small sample is highly valuable. We propose to observe a recently discovered CCO candidate with 90 ks. Due to the small angular size of the surrounding SNR, Chandra is the only instrument having sufficient angular resolution for the proposed analysis. We demonstrate that the new data will allow a confirmation/rejection of the CCO hypothesis and association with the SNR. If the CCO hypothesis is confirmed, we will use our atmosphere models to constrain the NS mass and radius.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+18:18:52.10	-15:02:13.90	CXOU J181852.0-150213	ACIS-I	None	90.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500414

Title: Investigating the nature of AX J1714.1-3912

Type: GO Total Time (ks): 10

PI Name: Marco Miceli

Abstract: Molecular clouds are predicted to emit non-thermal X-rays when they are close to particle-accelerating SNRs, but this emission has not been confirmed yet. We propose to observe the non-thermal X-ray source AX J1714.1-3912 to investigate its relationship with the nearby SNR RX J1713.7-3946. ASCA and Suzaku observations show that the spectrum of this source may be associated with extremely energetic particles accelerated in the SNR and diffusing in a nearby molecular cloud. This emission has never been observed in other SNRs. However, the association of the source with the remnant is still controversial and the available data cannot rule out a possible association with an AGN or an SFXT. We aim at verifying whether AX J1714.1-3912 is indeed an extended source to understand its nature.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+17:13:42.80	-39:12:15.40	AX J1714.1-3912	ACIS-I	None	10.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500418

Title: Mapping the Zoo of engine driven explosions with late-time X-rays

Type: TOO Total Time (ks): 50

PI Name: Raffaella Margutti

Abstract: We propose an in-depth study of a nearby long gamma-ray burst (GRB, z < 0.3) with Chandra. Our synergistic multi-wavelength effort (radio, optical, Swift/XRT and proposed Chandra) is designed to extract the true energy of these explosions and to reveal the activity of their central engines. This effort allows us to: (i) investigate whether sub-energetic GRBs share the same explosion mechanisms and central engines as ordinary GRBs; (ii) investigate what essential physical property enables only a small fraction of supernovae to harbor a relativistic outflow; (iii) understand if jet-driven explosions are common in all supernovae. These objectives are only possible by expanding the current small sample of local GRBs and by drawing comparisons with cosmological GRBs and ordinary SNe.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
		GRB1	ACIS-S	None	50.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500454

Title: Revisiting Vela shrapnel D: Understanding the dynamics of the SNR ejecta interaction with an interstellar cloud

Type: GO Total Time (ks): 30

PI Name: Fumiyoshi Kamitsukasa

Abstract: We propose to perform the second-epoch observation of Vela shrapnel D, a bullet of supernova ejecta overrunning the shock front of the Vela supernova remnant, to measure its proper motion. The shrapnel D is considered to be interacting with an interstellar cloud, which leads to the optical nebula, RCW 37. The shock velocity with the optical nebula is estimated as 100-200 km/s by the far-ultraviolet studies. The shock of the shrapnel D is, however, estimated to be as fast as ~ 500 km/s from both the electron temperature and the bow shock shape in X-rays. The key to understand this discrepancy is the proper motion in X-rays, which can be measured only with Chandra. We request one pointing observation with an exposure time of 30 ks.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+09:00:07.80	-45:50:42.70	Vela Shrapnel D revisit	ACIS-I	None	30.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500486

Title: HESS~J1640-465: Powering the most luminous gamma-ray source in the Galaxy

Type: GO Total Time (ks): 160

PI Name: Eric Gotthelf

Abstract: HESS 1640-465 is most luminous TeV source in the Galaxy and possibly the most efficient cosmic accelerator, yet the origin of its gamma-ray emission is uncertain. It lies near the center of the radio SNR G338.3-0.0, associated with hard Fermi emission, and is adjacent to a large HII region. Within the SNR resides a bright PWN powered by the newly discovered energetic pulsar PSR J1640-4631. The origin of the gamma-ray emission is difficult to discern, given the complex local environment, both leptonic and hadronic models for the emission mechanism have been argued. With the pulsar properties now in hand, we propose a deep Chandra observation of the PWN/SNR to help model its contribution to the broad-band spectrum of HESS J1640-65 and determine the origin of the gamma-rays in the region.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+16:40:43.50	-46:31:35.00	CXOU J164043.5-463135	ACIS-I	None	160.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500511

Title: Target-of-Opportunity Chandra Observations of Glitching High-B Radio Pulsars: Searching for Magnetar Metamorphoses

Type: TOO Total Time (ks): 1680

PI Name: Victoria Kaspi

Abstract: In 2006, observations of a high-magnetic-field rotation-powered pulsar (RPP) fortuitously caught a sudden transformation: we observed a "magnetar metamorphosis" simultaneous with a rotation glitch. The RPP's X-ray flux increased by a factor of 10, its spectrum changed dramatically, and it emitted magnetar-like X-ray bursts. After <8 weeks, it returned to its normal state. This amazing event, caught serendipitously, suggests that all high-magnetic-field RPPs may undergo transient metamorphoses at glitch epochs, but have not been so recognized because of the absence of a sensitive X-ray all-sky monitor. We therefore request Chandra ToO observations of one high-magnetic-field RPP when it has a large glitch or X-ray burst in order to test this hypothesis.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+01:57:49.90	+62:12:25.90	PSR B0154+61	ACIS-S	None	105.0
+07:26:08.10	-26:12:38.10	PSR J0726-2612	ACIS-S	None	105.0
+08:47:57.00	-43:16:57.20	PSR J0847-4316	ACIS-S	None	105.0
+11:19:14.30	-61:27:49.50	PSR J1119-6127	ACIS-S	None	105.0
+16:32:39.70	-48:18:52.60	PSR J1632-4818	ACIS-S	None	105.0
+17:18:10.00	-37:18:53.00	PSR J1718-3718	ACIS-S	None	105.0
+17:26:07.50	-35:29:58.00	PSR J1726-3530	ACIS-S	None	105.0
+17:34:26.60	-33:33:22.00	PSR J1734-3333	ACIS-S	None	105.0
+17:40:33.80	-30:15:43.50	PSR B1737-30	ACIS-S	None	105.0
+18:14:43.10	-17:44:48.00	PSR J1814-1744	ACIS-S	None	105.0
+18:19:33.80	-14:58:01.00	PSR J1819-1458	ACIS-S	None	105.0
+18:21:34.30	-14:19:26.00	PSR 1821-1419	ACIS-S	None	105.0
+18:47:35.20	-01:30:46.00	PSR J1847-0130	ACIS-S	None	105.0
+19:13:50.80	+04:46:06.00	PSR J1913+0446	ACIS-S	None	105.0
+19:18:23.60	+14:45:06.00	PSR B1916+14	ACIS-S	None	105.0
		New High-B pulsar	ACIS-S	None	105.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500533

Title: CHARACTERIZING A NEW RADIO FAINT SNR: G309.4-0.1

Type: GO Total Time (ks): 20

PI Name: Mark Reynolds

Abstract: We request a 20 ks observation of a new SNR, discovered during the Swift Galactic plane survey, with Chandra/ACIS-S3. This source has the lowest radio flux measured for a Galactic SNR to date, and would begin to probe the X-ray properties of the low radio flux distribution of Galactic SNRs, which have remained undiscovered at X-ray energies to date. The proposed observation will use the exquisite imaging capabilities of Chandra to provide constraints on the morphology, abundances and progenitor of this intriguing source.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+13:47:45.70	-62:14:11.00	G309.4-0.1	ACIS-S	None	20.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500534

Title: Energetics and Environment of Hydrogen-poor Core-Collapse SNe

Type: TOO Total Time (ks): 10

PI Name: Raffaella Margutti

Abstract: Envelope-stripped, core-collapse SNe (i.e. Type Ibc SNe) were recognized as a distinct flavor of core-collapse explosions 25 years ago. SNe Ibc have only recently enjoyed a surge of interest thanks to their association with Gamma-Ray Bursts (GRBs). The peculiar circumstances that enable a small fraction of SNe Ibc to launch a relativistic jet are not understood. Along the same line, the progenitors of SNe Ibc and their relation to those of GRBs have yet to be observationally identified. Here we propose a modest Chandra-VLA program to enable progress. The primary goals are to (i) populate the gap between ordinary type Ibc SNe and GRBs and (ii) to probe the diversity of the environment of ordinary SNe arising from envelope-stripped progenitors.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
		SN1	ACIS-S	None	10.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500556

Title: The puzzling dynamic nebula powered by the pulsar B1259-63 in a high-mass binary

Type: GO Total Time (ks): 130

PI Name: George Pavlov

Abstract: PSR B1259-63/LS 2883 is the famous eccentric gamma-ray binary (Pbin=3.4 yr, e=0.87) in which a pulsar orbits a massive O-type star. Its X-ray emission is produced by colliding winds of the pulsar and the massive companion. Using ACIS observations, we discovered an extended structure apparently moving away from the binary with v = 0.05-0.1 c. Such a moving X-ray nebula has never been seen before. To understand the nature of the dynamic nebula, the extended emission must be monitored throughout the binary orbit. As a first step in the monitoring program, we propose 2 ACIS observations to examine repeatability of the extended emission in different binary cycles and study the properties of the colliding winds and the emitting material.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+13:02:47.60	-63:50:08.70	PSR B1259-63	ACIS-I	None	65.0
+13:02:47.60	-63:50:08.70	PSR B1259-63	ACIS-I	None	65.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500634

Title: Snap-shot survey of unidentified Fermi sources

Type: GO Total Time (ks): 50

PI Name: Blagoy Rangelov

Abstract: We propose a mini-survey of unclassified Fermi sources from the 2FGL catalog. Using an intelligent parameter selection, we have identified a sub-sample that is likely to be dominated by pulsars with a possible inclusion of HMXBs. We aim to identify 5 new gamma-ray pulsars and their X-ray counterparts, and thus increase the population of pulsars detected in both gamma-rays and X-rays. The existing limited data hint at an intriguing change in the slope of the L(Edot) dependence at log(Edot)=35-36 erg/s. By identifying more pulsars in both gamma- and X-rays, we will be able to confirm the existence of those breaks and investigate their origin. We will also identify new X-ray bright pulsars suitable for detailed study using the prudent snap-shot approach.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+08:58:20.20	-43:33:34.60	2FGL J0858.3-4333	ACIS-I	None	10.0
+08:42:57.90	-47:21:53.30	2FGL J0842.9-4721	ACIS-I	None	10.0
+18:39:03.50	-01:02:07.00	2FGL J1839.0-0102	ACIS-I	None	10.0
+10:56:00.50	-58:53:16.80	2FGL J1056.0-5853	ACIS-I	None	10.0
+03:40:35.90	+53:07:52.90	2FGL J0340.5+5307	ACIS-I	None	10.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500640

Title: PROMPT STUDY OF MAGNETAR OUTBURSTS WITH CHANDRA

Type: TOO Total Time (ks): 2465

PI Name: Nanda Rea

Abstract: The discovery of transient magnetars has opened a new perspective in the field confirming that a relatively large number of members of this class has not been discovered yet, and suggesting that others would manifest themselves in the future through outbursts. This proposal is aimed at gathering new insights on the physics of magnetars through the study of their outbursts. In particular, we are asking for 85ks of Chandra time divided in 4 observations throughout the outburst from a known or still unknown magnetar candidate.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+00:00:00.00	+00:00:00.00	NEWMAGNETAR	ACIS-S	None	85.0
+18:09:51.10	-19:43:51.70	XTE J1810-197	ACIS-S	None	85.0
+01:00:43.10	-72:11:34.00	CXOUJ0100-7211	ACIS-S	None	85.0
+01:46:22.40	+61:45:03.30	4U0142+614	ACIS-S	None	85.0
+10:50:07.10	-59:53:21.40	1E1048.1-5937	ACIS-S	None	85.0
+17:08:46.00	-40:08:53.00	RXSJ170849-400910	ACIS-S	None	85.0
+18:41:19.40	-04:56:10.90	1E1841-04	ACIS-S	None	85.0
+18:44:54.70	-02:56:53.40	AXJ1844-0256	ACIS-S	None	85.0
+20:13:52.80	+34:19:55.20	SGR 2013+34	ACIS-S	None	85.0
+23:01:08.30	+58:52:44.50	1E 2259+584	ACIS-S	None	85.0
+19:07:14.30	+09:19:20.10	SGR 1900+14	ACIS-S	None	85.0
+16:35:51.80	-47:35:23.30	SGR 1627-41	ACIS-S	None	85.0
+18:08:39.30	-20:24:39.50	SGR 1806-20	ACIS-S	None	85.0
+05:26:00.90	-66:04:36.30	SGR 0526-66	ACIS-S	None	85.0
+05:01:06.20	+45:16:35.00	SGR 0501+4516	ACIS-S	None	85.0
+15:50:55.30	-54:19:02.00	1E 1547.0-5408	ACIS-S	None	85.0
+18:46:24.50	-02:58:28.00	PSR J1846-0258	ACIS-S	None	85.0
+04:18:33.90	+57:32:22.90	SGR 0418+4729	ACIS-S	None	85.0
+18:33:44.40	-08:31:07.70	SGR 1833-0832	ACIS-S	None	85.0
+16:22:44.80	-49:50:54.40	PSR 1622-4950	ACIS-S	None	85.0
+17:14:05.70	-38:10:30.90	CXO 171405-381031	ACIS-S	None	85.0
+18:34:52.10	-08:45:56.00	Swift 1834-0836	ACIS-S	None	85.0
+18:22:18.00	-16:04:26.80	Swift 1822-1606	ACIS-S	None	85.0
+16:47:10.20	-45:52:17.00	CXO J164710.2-455216	ACIS-S	None	85.0
+17:45:40.20	-29:00:29.80	SGR J1745-2900	ACIS-S	None	85.0
+18:52:46.60	+00:33:17.00	3XMM J185246.6+003317	ACIS-S	None	85.0
+18:18:51.40	-15:59:22.60	AX J1818.8-1559	ACIS-S	None	85.0
+18:08:11.20	-20:38:49.00	SGR 1808-20	ACIS-S	None	85.0
+18:00:59.00	-22:56:48.00	SGR 1801-23	ACIS-S	None	85.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500642

Title: A possible near-infrared counterpart for the isolated neutron star in the Carina Nebula

Type: GO Total Time (ks): 20

PI Name: Adriana Pires

Abstract: 2XMM J104608.7-594306 is one of only two thermally emitting isolated neutron stars (INSs) to be discovered since the ROSAT era. Likely a remnant of a former generation of massive stars in the Carina Nebula, its exact nature is unclear, and it might well occupy a unique role amongst the several groups of Galactic INSs. Very interestingly, we discovered a possible near-infrared counterpart lying inside the error circle of the X-ray source. We propose to observe the field of the neutron star with Chandra with the immediate goal to test the association. The positional accuracy attainable with Chandra will subsequently pave the ground for further investigations in the infrared and X-rays to be carried out, which will considerably constrain the neutron star evolutionary state.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+10:46:08.70	-59:43:06.50	2XMM J104608.7-594306	ACIS-S	None	20.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500703

Title: The cooling of the Cas A CCO: fast or slow?

Type: GO Total Time (ks): 78

PI Name: Bettina Posselt

Abstract: The cooling curve of a neutron star constrains the properties of the superdense matter in its interior. An exciting rapid cooling of the 330 yr old neutron star in the Cas A SNR was recently inferred from 7 Chandra observations of 2000-2012, which, unfortunately, suffered from serious systematic uncertainties. Two dedicated observations with an optimal observational setup, carried out by our team in 2006 and 2012, did not show a statistically significant temperature decay. However, at the 3 sigma level, the rapid cooling still cannot be completely ruled out. To firmly exclude or confirm the rapid cooling and establish a tight constraint on the cooling rate, we propose an additional dedicated observation of this object, undistorted by the systematic errors.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+23:23:27.90	+58:48:42.60	Cas A CCO	ACIS-S	None	78.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500705

Title: Nonuniform expansion and brightening of the youngest Galactic SNR G1.9+0.3

Type: LP Total Time (ks): 400

PI Name: Kazimierz Borkowski

Abstract: We propose a 400-ks observation of the youngest Galactic supernova remnant (SNR) G1.9+0.3, to study its nonuniform expansion and monitor increase in brightness. Expansion along the major axis of G1.9+0.3 has been found to decrease with radius. The longer time baseline should help in understanding these surprising variations in expansion. No other Galactic SNR is brightening. The X-rays are mainly produced as synchrotron radiation from 10 -- 100 TeV electrons, so the magnitude and spatial dependence of the brightening rate have important implications for the physics of particle acceleration and magnetic-field amplification in fast shock waves. G1.9+0.3 is a unique SNR whose continued monitoring should greatly advance our understanding of Type Ia supernovae and nonthermal shock physics.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+17:48:45.00	-27:10:00.10	G1.9+0.3	ACIS-S	None	400.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500718

Title: Expansion of Kes 73, a shell supernova remnant containing a magnetar

Type: GO Total Time (ks): 100

PI Name: Kazimierz Borkowski

Abstract: Formation and evolution of highly magnetized neutron stars (magnetars) remain poorly understood. We can learn about magnetars by studying their remnants. Kes 73 is a young supernova remnant containing a magnetar. But basic properties of Kes 73, including its age, remain poorly known. We propose a third-epoch observation of Kes 73 with Chandra. When combined with the 2000 and 2006 observations, this will allow for determination of the remnant's age through expansion rate measurements. We will also search for spatial variations in expansion rate that will help in understanding of the remnant's dynamics. New observations will also be used to determine abundances of heavy-element supernova ejecta, placing further constraints on the supernova that produced Kes 73.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+18:41:20.00	-04:56:11.00	Kes 73	ACIS-S	None	100.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500720

Title: IDENTIFY THE SIGNATURE OF NEUTRON STAR MERGERS THROUGH RAPID CHANDRA/HUBBLE OBSERVATIONS OF A SHORT GRB

Type: TOO Total Time (ks): 50

PI Name: Eleonora Troja

Abstract: The afterglow of some short GRBs displays a late-time rebrightening, visible a few days after the gamma-ray burst. Recent HST observations provided tantalizing evidence that such a late-time bump could be explained as the emergence of the underlying kilonova emission. This would represent the incontrovertible signature of a neutron star merger, and the first direct link between short GRBs and their progenitors. Here we ask for a rapid (few days) and deep Chandra/HST follow-up observation of a short duration GRB in order to detect the expected kilonova bump, and to constrain the origin of the observed emission. Multi-band observations, and in particular X-rays, are critical to pin down the nature of the observed rebrightening, and to distinguish it from the standard afterglow emission.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
		short GRB	ACIS-S	None	50.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500739

Title: (Re-)Constraining the Cosmic-Ray Acceleration Efficiency and Magnetic Field Strength in the Northeast Rims of RCW 86

Type: GO Total Time (ks): 70

PI Name: Hiroya Yamaguchi

Abstract: Accurate determination of SNR's shock velocity and magnetic filed is essential to reveal the mechanism of cosmic-ray acceleration. A previous velocity measurement with Chandra for the SNR RCW 86 northeast rim revealed that a substantial fraction of the postshock pressure is produced by the accelerated particles. However, there are disagreement with a H-alpha-measured velocity, and large uncertainty in the X-ray measurement itself, since the observation dates of the two Chandra datasets that were used for the proper motion measurement were not well separated with each other. We thus propose an additional observation of this region to measure the expansion velocity accurately. We will also constrain the magnetic field by searching for short-time variability in the synchrotron X-ray flux.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+14:45:03.60	-62:21:05.70	RCW 86 NE	ACIS-S	None	70.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500768

Title: The proper motion of the isolated neutron star RXJ0806.4-4123

Type: GO Total Time (ks): 35

PI Name: Bettina Posselt

Abstract: We propose a new Chandra epoch of the radio-quiet X-ray thermal isolated neutron star (XTINS) RXJ0806.4-4123 to check for X-ray variability, and to measure its proper motion which will enable a kinematic age study. The kinematic ages of XTINSs substantially deviate from their characteristic spin-down ages. Since the XTINSs allow to measure easily valuable surface temperatures, their correct ages are a mandatory requisite to assess the general cooling behavior of neutron stars. Based on the known close distance of RXJ0806.4-4123, a dedicated previous Chandra study, and simulations accounting for the changes in the ACIS detector, we estimate that a new 35ks Chandra exposure will constrain the minimum transverse velocity of the XTINS to better than 36km/s (3sigma).

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+08:06:23.40	-41:22:30.90	RXJ0806	ACIS-I	None	35.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500812

Title: New Chandra Observations of the Archetypical Mixed-Morphology Galactic Supernova Remnant W28 (G6.4-0.1)

Type: GO Total Time (ks): 50

PI Name: Thomas Pannuti

Abstract: We propose to conduct two new ACIS-I observations of the archetypical mixed-morphology Galactic supernova remnant W28. Our prior Chandra observation of this remnant sampled interior thermal X-ray emission which was more uniform than expected based on prior ROSAT and ASCA observations. We have also detected a new hard X-ray source in the southwestern portion of W28 which may be a pulsar associated with this remnant. Our new proposed observations will sample this hard source as well as the luminous northeastern rim of W28, the site of an interaction between the SNR and an adjacent molecular cloud. These observations will help us develop a more complete picture of W28 and other mixed-morphology SNRs as well.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+18:01:46.00	-23:15:41.00	W28 Northeast	ACIS-I	None	50.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500832

Title: X-RAY COUNTERPARTS OF PUZZLING GEV-TEV SOURCES

Type: GO Total Time (ks): 120

PI Name: Oleg Kargaltsev

Abstract: We propose to look for X-ray counterparts of the extended TeV source HESS J1616-508 that may also have been detected with Fermi at GeV energies. The nature of the source and the connection between the TeV source and the nearby GeV sources are unknown. It has been suggested that it may be a relic plerion powered by the offset PSR J1617-5055, but a deep Chandra observation of this pulsar and its wind nebula has not confirmed this hypothesis. To understand the nature of this long-standing "dark accelerator", we propose to observe the GeV sources (which could be young pulsars) and another nearby young pulsar (J1614-5048) to check whether or not they could supply relativistic particles and power the TeV source. We will also explore the nature of the GeV sources.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+16:14:12.60	-50:48:00.10	2FGL J1615.0-5051	ACIS-I	None	60.0
+16:16:10.20	-50:51:52.10	HESS J1616-508	ACIS-I	None	60.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500844

Title: Deep study on the proper motion and collimated tail of the oldish PSR J2055+2539

Type: GO Total Time (ks): 130

PI Name: Martino Marelli

Abstract: The bright, radio-quiet, and possibly near, J2055+2539 is the less energetic non-recycled pulsar emitting in gamma-rays. In X-rays we found the faint, pulsating counterpart. Two tails of X-ray emission have been discovered protruding from the pulsar forming an angle of about 150deg. These tails are long - 13' and 4' - bright - 10 and 2 times the pulsar luminosity - and extremely collimated - the longest one is 5 to 20'' wide. These characteristics make J2055 tails the best test for all the nebular emission models, making it a better case than fainter Guitar nebula. Two Chandra observations at different epochs are requested in order to a) find the pulsar proper motion, with a possible alignment with one of the tails, and b) study the shape and low-scale structures of the nebulae.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+20:55:50.60	+25:41:08.30	PSR J2055+2539 nebula	ACIS-S	None	130.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500869

Title: The Astrophysics of the Most Energetic Gamma-Ray Bursts

Type: TOO Total Time (ks): 120

PI Name: Andrew Fruchter

Abstract: The Large Area Telescope (LAT) of Fermi has found a sample of highly relativistic gamma-ray bursts (GRBs), which may be among the most energetic bursts ever discovered. Here we propose to use Chandra and HST to follow the late time X-ray and optical light curves of a LAT detected burst that also has excellent early multiwavelength coverage. Our observations, in conjunction with the Fermi data, will allow us to measure the energy and the bulk Lorentz factor of the explosion. Recent work on some of the most powerful GRBs begins to substantially constrain physical models of the progenitors. The energetics of the highly relativistic LAT bursts may greatly strengthen these constraints and provide new insight into the currently unknown mechanism that determines the energy of a GRB.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
		LAT Burst 1	ACIS-S	None	120.0

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 16500912

Title: The Burst of the Century

Type: GO Total Time (ks): 120

PI Name: Andrew Fruchter

Abstract: The extraordinarily bright GRB 130427A has provided a multiwavelength data set unprecedented in the history of the field. However the light curve of this burst, like that of the large majority of LAT bursts, shows a puzzling lack of a jet break (the hallmark of a collimated outflow). We propose to continue our long-term monitoring of this GRB through to the end of 2015. A detection of a jet break will give us a direct measure of the absolute energy of the burst; its absence will effectively rule out a rotating neutron star as the central engine of the GRB.

R.A.	Dec.	Target Name	Det.	Grating	Exp. Time (ks)
+11:32:32.80	+27:41:56.20	GRB 130427A	ACIS-S	None	120.0

The Chandra X-Ray Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA. Email: cxchelp@head.cfa.harvard.edu Smithsonian Institution, Copyright © 1998-2024. All rights reserved.