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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 2022-10-01) :

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 7718 60 104
2001 198 19365 217 439
2002 330 26364 380 1071
2003 431 29562 520 1828
2004 400 24511 497 2233
2005 447 26066 577 3093
2006 549 35896 687 2339
2007 498 28996 609 2258
2008 517 25901 672 4533
2009 430 23632 550 5443
2010 421 21950 532 4093
2011 440 20474 575 5924
2012 451 21386 547 7532
2013 426 19432 520 7659
2014 404 15584 482 6562
2015 428 15416 483 6957
2016 436 13957 516 7205
2017 471 17145 569 11041
2018 453 9781 503 7548
2019 420 5615 459 9533
2020 384 3400 407 6581
2021 336 1727 389 3989
Total 8925 413878 10751  

* 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