About Chandra Archive Proposer Instruments & Calibration Newsletters Data Analysis HelpDesk Calibration Database NASA Archives & Centers Chandra Science Links


Chandra Bibliographic Statistics

Tracking Scientific Productivity:

To evaluate the relative scientific effectiveness of Chandra observations, we have undertaken to compile and study data on related publications. Across institutions and even across disciplines, professional publications and citations represent the most commonly used and accepted method of tracking scientific productivity. See the March 2004 Newsletter article describing this effort.

Basic Annual Bibliographic Statistics (as of 2021-09-01) :

The basic annual bibliographic statistical data for the Chandra X-ray Observatory pertain to papers on Chandra observations. These papers fall into two groups: those that present specific Chandra observations (Category 1) and those that refer to published Chandra results with complementary observations, follow-up analysis, or theoretical analysis (Category 2 with flags A, B, or C). We define these as Chandra Science Papers.


Year Refereed
Chandra
Science
Papers
Number of
Citations
to these
Papers
All
Chandra
Science
Papers
Observations
Published
in Refereed
Papers *
2000 55 7548 60 104
2001 198 19019 216 439
2002 330 25877 375 1070
2003 431 28956 515 1825
2004 398 23598 490 2227
2005 446 25299 568 3093
2006 549 34633 679 2317
2007 498 27645 601 2201
2008 517 24961 661 4533
2009 429 22595 542 5452
2010 420 19294 521 4089
2011 439 16511 564 5894
2012 449 16887 529 7532
2013 426 14522 500 7660
2014 399 11021 466 6546
2015 428 10761 477 6983
2016 434 8601 495 7209
2017 473 9053 557 11063
2018 450 4024 489 7547
2019 418 841 442 9542
2020 381 0 390 6566
Total 8568 351646 10137  

* Note: this is a lower limit since it refers to Category 1 papers only.

The Chandra Bibliography Database:

The Chandra Bibliography Database allows the public to search all Chandra-related articles and to follow links from the data to the literature, as well as from the literature to the data. Thanks to the Astrophysics Data System (ADS), publication data are highly complete, and relatively easy to track. We query the ADS daily for publications related to Chandra or to X-ray astronomy, and we are complete from before Chandra's launch. We review the publications, categorize them by several different parameters, and enter them into the Bibliography Database. For publications that present, analyze, or refer to Chandra data, we determine the ObsIds involved (either from the text or by asking the authors). ObsIds allow links to other information, such as Chandra Proposal Database items like scientific category and proposal type.

(You Know What They Say About) Statistics:

The Chandra Biliography Database allows for the compilation of a large number of publication statistics. We create selected data tables and plots, linked below, which are updated monthly. The resulting plots and statistics have the potential for misinterpretation, unless one is alert to embedded assumptions and details affecting the tally. For instance, most plots linked here (except those by publication year) include only refereed journal articles that present specific Chandra observations, and all plots tally only programs whose observations are complete. We strongly recommend reading both the NOTES and CAVEATS and the DEFINITIONS and CONVENTIONS, as a guide for interpreting the plots linked below. If you have pressing questions or concerns, please contact Paul Green of the Chandra Director's Office.

Plots and Data:

Refereed Chandra Science Papers by Publication Year
Citations to Refereed Chandra Science Papers by Publication Year
Plots and Data for Category 1 papers only

Supporting Documents:

NOTES and CAVEATS
DEFINITIONS and CONVENTIONS