Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

11847 results found.

  1. Fermi trigger No 588350802 Global MASTER-Net observations report
  2. GRB 190823A: MAXI/GSC detection
  3. Fermi trigger No 588185734 Global MASTER-Net observations report
  4. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  5. Fermi trigger No 588115134 Global MASTER-Net observations report
  6. LIGO/Virgo S190814bv: No radio counterpart detected in ASKAP observations
  7. LIGO/Virgo S190822c: CLU/NED Galaxies in the 50% Localization Volume
  8. LIGO/Virgo S190814bv: new candidate from DESGW
  9. LIGO/Virgo S190814bv: No Optical Counterpart Candidates in Second-Epoch Lick/KAIT Observations
  10. Swift GRB190821.72 Global MASTER-Net observations report
  11. Fermi trigger No 588100239 Global MASTER-Net observations report
  12. Fermi GBM-190816: No counterpart candidates in Fermi-LAT observations
  13. LIGO/Virgo S190814bv: further candidates from DESGW
  14. Fermi-LAT Gamma-ray Observations of IceCube-190819A
  15. LIGO/Virgo S190814bv: AT2019nqq 10.4m GTC spectroscopy
  16. IceCube-190819A: Upper limits from a search for additional neutrino events in IceCube
  17. Fermi GBM-190816: No counterpart candidates in HAWC observations
  18. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  19. LIGO/Virgo S190814bv: GRAWITA TNG NIR imaging of AT2019nqq and AT2019nqc
  20. LIGO/Virgo S190814bv: No strong counterpart candidates in Swift/XRT observations
  21. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  22. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  23. LIGO/Virgo S190814bv : ENGRAVE X-shooter spectra of AT2019nqs and AT2019npy
  24. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  25. LIGO/Virgo S190814bv : No Counterpart Candidates in Continued Galaxy Targeted Search with Magellan
  26. Baksan Neutrino Observatory Alert 190816.83 Global MASTER-Net observations report
  27. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  28. SUBJECT: LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations
  29. S190814bv: MASTER analysis of DECam-GROWTH candidates
  30. LIGO/Virgo S190814bv: Konus-Wind observations
  31. LIGO/Virgo S190814bv: Upper limits from Insight-HXMT/HE observations
  32. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  33. Fermi trigger No 587505927 Global MASTER-Net observations report
  34. LIGO/VIRGO S190814bv: No candidates from Pan-STARRS and non-detection of AT2019nme
  35. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  36. LIGO/Virgo S190814bv: No Counterparts in DDOTI/OAN Optical Observations
  37. LIGO/Virgo S190814bv: no counterpart candidates in Thacher imaging
  38. LIGO/Virgo S190814bv: no counterpart candidates in Nickel/Direct imaging and non-detections of 2019nmd and 2019nme
  39. LIGO/Virgo S190814bv: no counterpart candidates in Keck I MOSFIRE imaging
  40. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  41. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  42. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  43. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  44. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  45. GRB 190814A: Fermi GBM Final Real-time Localization
  46. HAWC-190806A: Upper limits from Insight-HXMT/HE observations
  47. FRB 190806: MASTER optical observation
  48. Konus-Wind observation of GRB 190810A
  49. HAWC-190806A: upper limits from INTEGRAL SPI-ACS and IBIS prompt observation
  50. HAWC Burst Alert 1008846_957: Konus-Wind observations
  51. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  52. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  53. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  54. HAWC Burst Alert 1008846_957: IceCube Neutrino Search
  55. Konus-Wind observation of GRB 190805B
  56. Alert from the HAWC Burst Monitor
  57. Fermi trigger No 586676451 Global MASTER-Net observations report
  58. Konus-Wind observation of GRB 190731A
  59. GRB 190805B: MAXI/GSC detection
  60. Fermi trigger No 586638042 Global MASTER-Net observations report
  61. MAXI GRB190804.33 Global MASTER-Net observations report
  62. GRB 190804B: MAXI/GSC detection
  63. LIGO/Virgo S190728q: AT2019lzc 10.4m GTC spectroscopy
  64. Fermi trigger No 586574612 Global MASTER-Net observations report
  65. GRB 190731A: AstroSat CZTI detection
  66. GRB 190731A: no OT detected by MASTER
  67. GRB 190719C: VLT/X-shooter spectroscopic redshift of the host galaxy
  68. GRB 190731A: Swift-XRT afterglow detection
  69. IPN Triangulation of GRB 190731A
  70. GRB 190726B: AstroSat CZTI detection
  71. GRB190731A: Fermi-LAT detection
  72. Fermi trigger No 586305505 Global MASTER-Net observations report
  73. IceCube-190730A: Upper limits from a search for additional neutrino events in IceCube
  74. GRB 190731A: Fermi GBM Final Real-time Localization
  75. Fermi-LAT Gamma-ray Observations of IceCube-190730A
  76. IceCube-190730A - HAWC follow-up
  77. LIGO/Virgo S190728q: No counterpart candidates in H.E.S.S. observations
  78. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  79. IceCube 190730A: one weakly associated counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  80. IceCube-190730A: MASTER optical observation
  81. LIGO/Virgo S190707q: AstroSat CZTI upper limits
  82. LIGO/Virgo S190718y: AstroSat CZTI upper limits
  83. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  84. LIGO/Virgo S190720a: AstroSat CZTI upper limits
  85. IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
  86. LIGO/Virgo S190728q: Optical transients from Pan-STARRS coverage during first 2 nights
  87. Konus-Wind observation of GRB 190727B
  88. S190728q: MASTER multiple previous outbursts detection of ZTF19abjethn=AT2019lvs
  89. LIGO/Virgo S190728q: No counterpart candidates in KAIT observations
  90. LIGO/Virgo S190728q: ZTF19abjethn TShAO and NUTTelA-TAO optical observations / classification
  91. GRB 190727B: Swift-BAT refined analysis
  92. LIGO/Virgo S190728q: Classification of AT2019lvs/ZTF19abjethn as a CV
  93. LIGO/Virgo S190728q: Pan-STARRS detection of the transient AT2019lvs/ZTF19abjethn 18hrs before S190728q
  94. LIGO/Virgo S190728q: No counterpart candidates in Fermi-LAT observations
  95. LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
  96. LIGO/Virgo S190728q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  97. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  98. GRB 190727B: Fermi-LAT detection
  99. Fermi trigger No 585988241 Global MASTER-Net observations report
  100. GRB 190727B: Fermi GBM observations

Advanced

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