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"

28045 results found.

  1. LIGO/Virgo S191205ah: Upper limits from Konus-Wind observations
  2. LIGO/Virgo S191204r: Upper limits from Konus-Wind observations
  3. LIGO/Virgo S191129u: Upper limits from Konus-Wind observations
  4. Fermi-LAT Gamma-ray Observations of IceCube-200117A
  5. LIGO/Virgo S200115j : No significant candidates in TAROT - FRAM - GRANDMA observations
  6. LIGO/Virgo S200115j: Mondy upper limits for ZTF20aafqvyc/AT2020yq
  7. GRB 200115A: Mondy optical observations and correction to GCN 26790
  8. LIGO/Virgo S200115j: LCO upper limits for ZTF20aafqvyc/AT2020yq from the McDonald Observatory 1-m telescope
  9. IceCube-200117A : Upper limits from Insight-HXMT/HE observations
  10. LIGO/Virgo S200115j: NIR upper limits for ZTF20aafqvyc/AT2020yq from the Palomar 200-inch telescope
  11. IceCube-200117A: Candidate Counterpart from the Zwicky Transient Facility
  12. IceCube-200117A: Upper limits from a search for additional neutrino events in IceCube
  13. IceCube-200117A: No Neutrino Counterpart in ANTARES data
  14. LIGO/Virgo S200105ae: More candidates from the Zwicky Transient Facility
  15. LIGO/Virgo S200115j: Updated Sky Localization and source properties
  16. IceCube-200117A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  17. LIGO/Virgo S200114f: No transients found in J-GEM observations of nearby galaxies
  18. GRB 200115A: AROMA-N Optical Observation
  19. LIGO/Virgo S200115j: Swift-XRT sources
  20. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  21. LIGO/Virgo S200114f: Upper Limits from Wide-Field Infrared Search with Palomar Gattini-IR
  22. GRB 200115A: DDOTI/OAN optical observations report
  23. GRB 200115A: Mondy optical afterglow candidate
  24. LIGO/Virgo S200112r : No significant candidates in TAROT - FRAM - GRANDMA observations.
  25. LIGO/Virgo S200115j: No neutrino candidates at Pierre Auger Observatory
  26. LIGO/Virgo S200114f: Swift-XRT sources and observations
  27. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  28. GRB 200115A: Swift-BAT refined analysis
  29. LIGO/Virgo S200115j: no counterpart candidates in the Swift/BAT observations
  30. IPN triangulation of GRB 200111A
  31. LIGO/Virgo S200115j High Rank XRT sources are spurious
  32. LIGO/Virgo S200115j: No counterpart candidates in Fermi-LAT observations
  33. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  34. GRB 200114A: Insight-HXMT/HE detection
  35. GRB 200115A: Nanshan-0.6m optical upper limit
  36. LIGO/Virgo S200115j: upper limits from AGILE/GRID observations
  37. LIGO/Virgo S200115j: upper limits from AGILE/MCAL observations
  38. LIGO/Virgo S200115j : no neutrino counterpart candidate in ANTARES search
  39. LIGO/Virgo S200115j: Coverage and upper limits from MAXI/GSC observations
  40. LIGO/Virgo S200115j: Identification of a GW compact binary merger candidate
  41. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  42. LIGO/Virgo S200115j: Upper limits from IceCube neutrino searches
  43. GRB 200114A: DDOTI/OAN optical observations report
  44. LIGO/Virgo S200114f: No Counterparts in DDOTI/OAN Optical Observations
  45. LIGO/Virgo S200114f: Constraints on a CCSN origin from KM3NeT MeV neutrino search.
  46. LIGO/Virgo S200114f: upper limits from AGILE-GRID observations
  47. LIGO/Virgo S200114f: no counterpart candidates in the Swift/BAT observations
  48. IceCube-200109A: Candidate Counterparts from the Zwicky Transient Facility
  49. LIGO/Virgo S200114f: No counterpart candidates in Fermi-LAT observations
  50. LIGO/Virgo S200114f: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  51. LIGO/Virgo S200114f : no neutrino counterpart candidate in ANTARES search
  52. LIGO/Virgo S200114f: Coverage and upper limits from MAXI/GSC observations
  53. GRB 200114A: BALROG localization (Fermi Trigger 600666048 / GRB 200114153)
  54. LIGO/Virgo S200114f: Identification of a GW unmodeled transient candidate
  55. LIGO/Virgo S200114f: No counterpart candidates in HAWC observations
  56. LIGO/Virgo S200114f: Upper limits from IceCube neutrino searches
  57. LIGO/Virgo S200112r: Upper limits from Insight-HXMT/HE observations
  58. Fermi-LAT Gamma-ray Observations of IceCube-200109A and detection of a possible new gamma-ray source, Fermi J1055.8+1034
  59. LIGO/Virgo 200112r: No counterpart candidates in Fermi-LAT observations
  60. LIGO/Virgo S200112r: upper limits from AGILE/GRID observations
  61. LIGO/Virgo S200112r: upper limits from AGILE/MCAL observations
  62. LIGO/Virgo S200112r: Coverage and upper limits from MAXI/GSC observations
  63. LIGO/Virgo S200112r: No counterpart candidates in HAWC observations
  64. LIGO/Virgo S200112r : no neutrino counterpart candidate in ANTARES search
  65. LIGO/Virgo S200112r: Upper limits from IceCube neutrino searches
  66. LIGO/Virgo S200112r: Identification of a GW compact binary merger candidate
  67. GRB 200111A: Insight-HXMT/HE detection
  68. GRB 200112A: BALROG localization (Fermi Trigger 600525396 / GRB 200112525)
  69. GRB 200109A: Insight-HXMT/HE detection
  70. IceCube 200109A: No significant detection in HAWC
  71. Fermi-LAT ANTARES coincidence: No significant detection in HAWC
  72. IceCube-200109A: Upper limits from a search for additional neutrino events in IceCube
  73. IceCube-200107A: Upper limits from a search for additional neutrino events in IceCube
  74. IceCube-200109A: Swift-XRT and UVoT Follow-up Observations
  75. ANTARES 200108A: No detection by Swift-XRT
  76. GRB 200107B: Swift/UVOT Observations
  77. GRB 200109A: Swift-BAT refined analysis
  78. Swift follow-up observations of IceCube-200107A: Identification of X-ray high state for 4FGL J0955.1+3551
  79. GRB 200109A: Swift/UVOT Upper Limits
  80. GRB 200109A: Fermi GBM observation
  81. LIGO/Virgo S200105ae: Updated Sky Localization and EM-Bright Probabilities
  82. LIGO/Virgo S200105ae : No significant candidates in TAROT - FRAM - GRANDMA observations.
  83. GRB 200107B: Swift-XRT refined Analysis
  84. Fermi-LAT ANTARES coincidence: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  85. GRB 200109A: Swift-XRT refined Analysis
  86. GRB 200109A: Enhanced Swift-XRT position
  87. GRB 200109A: Swift detection of a burst
  88. Fermi-LAT ANTARES coincidence
  89. LIGO/Virgo S200105ae: Candidates from the Zwicky Transient Facility
  90. GRB 200107B: Fermi GBM observation
  91. GRB 200107B: Swift-BAT refined analysis
  92. Fermi-LAT Gamma-ray Observations of IceCube-200107A
  93. IceCube-200107A: No significant detection in HAWC
  94. IceCube-200107A: No candidates from the Zwicky Transient Facility
  95. IceCube-200107A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  96. GRB 200101A: CALET Gamma-Ray Burst Monitor detection
  97. GRB 200107B: Swift detection of a burst
  98. IceCube-200107A: IceCube observation of a high-energy neutrino candidate event
  99. LIGO/Virgo 200105ae: No counterpart candidates in Fermi-LAT observations
  100. LIGO/Virgo S200105ae: AstroSat CZTI upper limits

Advanced

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