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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"

8497 results found.

  1. LIGO/Virgo S200224ca: Identification of a GW compact binary merger candidate The LIGO Scientific Collaboration and the Virgo Collaboration
  2. GRB 200219C: Swift-XRT afterglow confirmation
  3. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  4. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC observations
  5. GRB 200219C: Mondy and TSHAO optical observations
  6. GRB 200219C: DDOTI Observations
  7. GRB 200219C: Tiled Swift observations
  8. LIGO/Virgo S200219ac: Fermi GBM transient event not confidently associated with GW signal
  9. LIGO/Virgo S200219ac: upper limits from AGILE/GRID observations
  10. LIGO/Virgo S200219ac : no neutrino counterpart candidate in ANTARES search
  11. LIGO/Virgo S200219ac: Upper limits from IceCube neutrino searches
  12. LIGO/Virgo S200219ac: No counterpart candidates in HAWC observations
  13. LIGO/Virgo S200219ac: Identification of a GW compact binary merger candidate
  14. GRB 200219A: MASTER catalog automatic possible Host Galaxy candidate
  15. GRB 200219A: Swift detection of a short burst
  16. LIGO/Virgo (S200213t/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
  17. GRB 200216B - possible IR counterpart from VLT
  18. GRB 200216B: Swift detection of a burst
  19. LIGO/Virgo S200213t: Updated Sky Localization
  20. LIGO/Virgo S200213t: Updated coverage and candidate list for the Zwicky Transient Facility
  21. LIGO/Virgo S200213t: CLU/NED Galaxies in the 4-Update Localization Volume
  22. LIGO/Virgo S200213t: Updated Sky Localization
  23. LIGO/Virgo S200213t: Lulin Follow-Up Observations
  24. GRB 200215A: Swift detection of a burst
  25. LIGO/Virgo S200213t: MASTER possible Kilonova candidate in PGC315337
  26. LIGO/Virgo S200213t: P200 Spectroscopy of ZTF20aanakcd/AT2020cmr
  27. LIGO/Virgo S200213t: No counterpart candidates from Nanshan-0.6m observations
  28. LIGO/Virgo S200213t: No notable candidates in GOTO imaging
  29. LIGO/Virgo S200213t: One additional candidate from the Zwicky Transient Facility
  30. LIGO/Virgo S200213t: upper limits from AGILE/GRID observations
  31. LIGO/Virgo S200208q: no counterpart candidate in SVOM/C-GFT observations
  32. LIGO/Virgo S200213t : no neutrino counterpart candidate in ANTARES search
  33. LIGO/Virgo S200213t: Neutrino and galaxies cross-match
  34. LIGO/Virgo S200213t: NED Galaxies in the 90% Localization Volume
  35. LIGO/Virgo S200213t: 1 counterpart neutrino candidate from IceCube neutrino searches
  36. LIGO/Virgo S200213t: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo S200208q: Updated Sky Localization
  38. LIGO/Virgo S200208q: Not observable by CALET
  39. LIGO/Virgo S200208q: Upper limits from Fermi-GBM Observations
  40. LIGO/Virgo S200208q : upper limits from AGILE/GRID observations
  41. LIGO/Virgo S200208q: No counterpart candidates in HAWC observations
  42. LIGO/Virgo S200208q : no neutrino counterpart candidate in ANTARES search
  43. LIGO/Virgo S200208q: Upper limits from IceCube neutrino searches
  44. LIGO/Virgo S200208q: Identification of a GW compact binary merger candidate
  45. Swift Trigger 954840 is not a GRB
  46. GRB 200205A = Swift J0840.7-3516, A newly discovered transient X-ray Pulsar
  47. GRB 200205B: Swift detection of a burst with optical counterpart
  48. AMON IceCube-HAWC_200202A : No neutrino counterpart seen with ANTARES
  49. GRB 200131A: Swift detection of a burst with an optical counterpart
  50. LIGO/Virgo S200128d: no counterpart candidate in SVOM/GWAC observations
  51. LIGO/Virgo S200129m: Upper limits from CALET observations.
  52. LIGO/Virgo S200129m: NED Galaxies in the 50% Localization Volume
  53. LIGO/Virgo S200128d: upper limits from AGILE/GRID observations
  54. LIGO/Virgo S200129m: upper limits from AGILE/GRID observations
  55. LIGO/Virgo S200129m: Upper limits from IceCube neutrino searches
  56. LIGO/Virgo S200129m: Identification of a GW compact binary merger candidate
  57. Fermi-LAT ANTARES coincidence: IceCube neutrino search
  58. LIGO/Virgo S200128d: Upper limits from Fermi-GBM Observations
  59. LIGO/Virgo S200128d : no neutrino counterpart candidate in ANTARES search
  60. LIGO/Virgo S200128d: No counterpart candidates in HAWC observations
  61. LIGO/Virgo S200128d: Identification of a GW compact binary merger candidate
  62. LIGO/Virgo S200128d: Upper limits from IceCube neutrino searches
  63. GRB 200127A: Swift detection of a burst
  64. GRB 200125A: AbAO optical upper limit
  65. GRB 200125A: TNG detection of a NIR counterpart candidate
  66. IceCube-200120A: Event likely due to background
  67. GRB 200115A: Assy optical observations
  68. LIGO/Virgo S200115j: Zwicky Transient Facility search for optical counterparts to Swift X-ray sources
  69. IPN Triangulation of GRB 200120A
  70. GRB 200122A: GOTO non-detection of optical afterglow
  71. GRB 200122A: Swift detection of a burst
  72. IceCube-200120A: Upper limits from a search for additional neutrino events in IceCube
  73. IceCube-200120A: not observable by Fermi-GBM
  74. IceCube-200120A: IceCube observation of a high-energy neutrino candidate event
  75. IceCube 200117A: No significant detection in HAWC
  76. LIGO/Virgo S200115j: No counterpart detection within possible host galaxies observed by the GRAWITA-Savelli telescope
  77. GRB 200115A: Mondy optical observations and correction to GCN 26790
  78. IceCube-200117A: One Additional Candidate Counterpart from the Zwicky Transient Facility
  79. IceCube-200117A: Candidate Counterpart from the Zwicky Transient Facility
  80. IceCube-200117A: Upper limits from a search for additional neutrino events in IceCube
  81. IceCube-200117A: No Neutrino Counterpart in ANTARES data
  82. LIGO/Virgo S200115j: Updated Sky Localization and source properties
  83. LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
  84. IceCube-200117A: Upper limits from Fermi-GBM Observations
  85. IceCube-200117A: IceCube observation of a high-energy neutrino candidate event
  86. LIGO/Virgo S200115j: Upper limits from CALET observations.
  87. LIGO/Virgo S200114f: ZTF Forced Photometry of the Swift Source S200114f_X2
  88. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  89. LIGO/Virgo S200114f: Possible X-ray transient
  90. GRB 200115A: Mondy optical afterglow candidate
  91. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  92. LIGO/Virgo S200116ah: Retraction of GW compact binary merger candidate
  93. LIGO/Virgo S200115j High Rank XRT sources are spurious
  94. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  95. LIGO/Virgo S200115j: upper limits from AGILE/GRID observations
  96. LIGO/Virgo S200115j : no neutrino counterpart candidate in ANTARES search
  97. LIGO/Virgo S200114f: Upper limits from CALET observations.
  98. LIGO/Virgo S200115j: Identification of a GW compact binary merger candidate
  99. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  100. LIGO/Virgo S200115j: Upper limits from IceCube neutrino searches

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