Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

4057 results found.

  1. LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
  2. LIGO/Virgo S190910h: Upper limits from Fermi-GBM Observations
  3. LIGO/Virgo S190910h: No counterpart candidates in AGILE-MCAL observations
  4. LIGO/Virgo S190910h Global MASTER-Net observations report
  5. LIGO/Virgo S190910h : no neutrino counterpart candidate in ANTARES search
  6. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  7. LIGO/Virgo S190910h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  8. LIGO/Virgo S190910h: Upper limits from IceCube neutrino searches
  9. LIGO/Virgo S190910h: Identification of a GW compact binary merger candidate
  10. LIGO/Virgo S190910d: Candidates from the Zwicky Transient Facility
  11. LIGO/Virgo S190910d: no counterpart candidates in AGILE-GRID observations
  12. LIGO/Virgo S190910d: no counterpart candidates in the Swift/BAT Observations
  13. LIGO/Virgo S190910d: No counterpart candidates in AGILE-MCAL observations
  14. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S190910d : no neutrino counterpart candidate in ANTARES search
  16. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  17. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
  19. LIGO/Virgo S190910d: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo S190910d Global MASTER-Net observations report
  21. LIGO/Virgo S190910d: Upper limits from IceCube neutrino searches
  22. LIGO/Virgo S190814bv: ATCA monitoring of ASKAP J005547-270433/AT2019osy
  23. LIGO/Virgo S190814bv: VLA/JAGWAR monitoring of the 50% containment region
  24. LIGO/Virgo S190901ap: Gaia Photometric Alerts transient candidates
  25. LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
  26. LIGO/Virgo S190901ap: ZTF19abwvals is a type-Ia SN near maximum
  27. LIGO/Virgo S190901ap: Second Epoch Hobby-Eberly Telescope observations of ZTF19abvionh
  28. LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
  29. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  30. LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv
  31. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  32. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate MASTER OT J171434.95+280725.6
  33. LIGO/Virgo S190901ap: Dabancheng-0.5m optical observations of AT2019pjv
  34. LIGO/Virgo S190901ap: Additional candidates from the Zwicky Transient Facility
  35. LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
  36. LIGO/Virgo S190901ap: GTC follow-up spectroscopic observations of ZTF19abvizsw
  37. LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
  38. LIGO/Virgo S190901ap: MASTER OT J171434.95+280725.6/AT2019pjv detection
  39. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  40. LIGO/Virgo S190901ap: Upper limits from CALET observations.
  41. LIGO/Virgo S190901ap: Upper limits from Insight-HXMT/HE observations
  42. LIGO/Virgo S190901ap : SVOM/GWAC-F60A observation of transient ZTFabvizsw
  43. LIGO/Virgo S190901ap: Keck I LRIS spectroscopy of ZTF19abvizsw
  44. LIGO/Virgo S190901ap: Keck I LRIS spectroscopy of ZTF19abvionh
  45. LIGO/Virgo S190901ap: Additional observations from the Zwicky Transient Facility
  46. LIGO/Virgo S190901ap: GROWTH-India follow-up of ZTF19abvionh
  47. LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
  48. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  49. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  50. LIGO/Virgo S190901ap: No neutrino candidates at Pierre Auger Observatory
  51. LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
  52. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh [correction on the peak]
  53. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh
  54. LIGO/Virgo S190814bv: ATCA observation of ASKAP J005547-270433/AT2019osy
  55. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of target galaxy; no obvious optical counterpart.
  56. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate ZTFabvixoy
  57. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate ZTFabvizsw
  58. LIGO/Virgo S190901ap: no counterpart candidates in the Swift/BAT Observations
  59. LIGO/Virgo S190901ap: Candidates from the Zwicky Transient Facility
  60. LIGO/Virgo S190901ap: Updated Sky Localization
  61. LIGO/Virgo S190901ap: No counterpart candidates in AGILE-MCAL observations
  62. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  63. LIGO/Virgo S190901ap : no neutrino counterpart candidate in ANTARES search
  64. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  65. LIGO/Virgo S190901ap Global MASTER-Net observations report
  66. LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
  67. LIGO/Virgo S190901ap: Identification of a GW compact binary merger candidate
  68. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  69. LIGO/Virgo S190901ap: Upper limits from IceCube neutrino searches
  70. LIGO/Virgo S190814bv : No significant candidates in TAROT-GRANDMA observations
  71. LIGO/Virgo S190814bv: LCO Photometry of desgw-190814f/AT2019nte
  72. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidate AT2019ntp
  73. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  74. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  75. LIGO/Virgo S190814bv: AT2019odc and AT2019omt 10.4m GTC spectroscopy
  76. LIGO/Virgo S190814bv: AT2019nqc and AT2019nqz 10.4m GTC spectroscopy
  77. LIGO/Virgo S190828j: No Counterparts in DDOTI/OAN Optical Observations
  78. LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
  79. LIGO/Virgo S190814bv: Upper limits from a two-week IceCube search for neutrinos from the direction of ASKAP J005547-270433
  80. LIGO/Virgo S190829u Global MASTER-Net observations report
  81. LIGO/Virgo S190829u: Retraction of GW compact binary merger candidate
  82. LIGO/Virgo S190426c: Update on Probability of Terrestrial Origin
  83. LIGO/Virgo S190828l: Upper limits from Insight-HXMT/HE observations
  84. LIGO/Virgo S190814bv: Swift observation of ASKAP J005547-270433/AT2019osy
  85. LIGO/Virgo S190814bv: AT2019nxe and AT2019obc 10.4m GTC spectroscopy
  86. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidates AT2019ntr and AT2019omx
  87. LIGO/Virgo S190814bv: VLA observation of ASKAP J005547-270433/AT2019osy
  88. LIGO/Virgo S190828l: No counterpart candidates in Fermi-LAT observations
  89. LIGO/Virgo S190828l: No transient candidates in CALET observations
  90. LIGO/Virgo S190828j: No transient candidates in CALET observations
  91. LIGO/Virgo S190828l: no counterpart candidates in the Swift/BAT Observations
  92. LIGO/Virgo S190828j: no counterpart candidates in the Swift/BAT Observations
  93. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  94. LIGO/Virgo S190828j: No counterpart candidates in Fermi-LAT observations
  95. LIGO/Virgo S190814bv: no variation of DESGW candidates AT 2019onj and AT 2019okr from ENGRAVE VLT/HAWK-I observations, and archival detection
  96. LIGO/Virgo S190814bv: Swift UVOT - no new counterpart candidates identified
  97. LIGO/Virgo S190828l: Upper limits from Fermi-GBM Observations
  98. LIGO/Virgo S190828j: Upper limits from Fermi-GBM Observations
  99. LIGO/Virgo S190828l: Upper limits from AGILE-GRID observations
  100. LIGO/Virgo S190828l: Upper limits from IceCube neutrino searches

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov