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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"

24565 results found.

  1. GRB 230710A: Fermi GBM Final Real-time Localization
  2. LIGO/Virgo/KAGRA S230708z: Identification of a GW compact binary merger candidate
  3. LIGO/Virgo/KAGRA S230708t: Identification of a GW compact binary merger candidate
  4. IceCube-230707A: No candidates detected by Swift-XRT
  5. GRB 230709C: AstroSat CZTI detection
  6. LIGO/Virgo/KAGRA S230708cf: Updated Sky localization
  7. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  8. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  9. LIGO/Virgo/KAGRA S230707ai: Updated Sky localization
  10. IceCube-230707A: No candidates from the Zwicky Transient Facility
  11. Fermi-LAT gamma-ray observations of IceCube-230708A
  12. Fermi-LAT gamma-ray observations of IceCube-230707B
  13. Fermi-LAT gamma-ray observations of IceCube-230707A
  14. LIGO/Virgo/KAGRA S230630am: Updated Sky localization
  15. LIGO/Virgo/KAGRA S230630am: Updated Sky localization
  16. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  17. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  18. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  19. IceCube-230707A: Upper limits from a search for additional neutrino events in IceCube
  20. LIGO/Virgo/KAGRA S230709bi: Identification of a GW compact binary merger candidate
  21. Swift Trigger 1178410: possible GRB 230709A
  22. LIGO/Virgo/KAGRA S230708cf: Identification of a GW compact binary merger candidate
  23. GRB 230628C: GRID Detection
  24. IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
  25. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  26. IceCube Alert 230708.35: Global MASTER-Net observations report
  27. IceCube-230707B - IceCube observation of a high-energy neutrino candidate track-like event
  28. GRB 230707B: Fermi GBM Final Real-time Localization
  29. IceCube Alert 230707.71: Global MASTER-Net observations report
  30. IceCube-230707A - IceCube observation of a high-energy neutrino candidate track-like event
  31. GRB 230707A: Fermi GBM Detection
  32. LIGO/Virgo/KAGRA S230707ai: Identification of a GW compact binary merger candidate
  33. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  34. Fermi GRB 230707A: Global MASTER-Net observations report
  35. GRB 230707A: Fermi GBM Final Real-time Localization
  36. LIGO/Virgo/KAGRA S230706ah: Updated Sky localization
  37. Integral GRB230706.70: Global MASTER-Net observations report
  38. LIGO/Virgo/KAGRA S230704f: Updated Sky localization
  39. LIGO/Virgo/KAGRA S230630bq: Updated Sky localization
  40. IBAS trigger number 10311: not a real GRB
  41. LIGO/Virgo/KAGRA S230702an: Updated Sky localization
  42. GRB 230625A: Detection by GRID
  43. LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
  44. LIGO/Virgo/KAGRA S230706ah: Identification of a GW compact binary merger candidate
  45. LIGO/Virgo/KAGRA S230627c: GECKO optical follow-up observations of host galaxy candidates and ZTF23aaptsuy/AT2023lxu
  46. Fermi trigger No 710117592: Global MASTER-Net observations report
  47. GRB 230626A: VZLUSAT-2 detection
  48. LVK S230619bd/GBM-230619: Upper limits from a two-week IceCube neutrino search
  49. LIGO/Virgo/KAGRA S230704f: Identification of a GW compact binary merger candidate
  50. Konus-Wind detection of GRB 220623A
  51. LIGO/Virgo/KAGRA S230627c: observations of ZTF23aaptsuy/AT2023lx in AbAO observatory
  52. LIGO/Virgo/KAGRA S230702an: Identification of a GW compact binary merger candidate
  53. GRB 230628E: Swift-BAT refined analysis
  54. GRB 230702A: Fermi GBM Final Real-time Localization
  55. GRB 230701A: Fermi GBM Final Real-time Localization
  56. LIGO/Virgo/KAGRA S230627c: GRANDMA observations of galaxies and ZTF counterpart candidates
  57. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230701z: one counterpart neutrino candidate from IceCube neutrino searches
  58. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  59. LIGO/Virgo/KAGRA S230630bq: Identification of a GW compact binary merger candidate
  60. IPN triangulation of GRB 230625B (ultra-long)
  61. LIGO/Virgo/KAGRA S230630am: Identification of a GW compact binary merger candidate
  62. GRB 230628E - VLT spectroscopic observations
  63. Fermi GRB 230628C: Global MASTER-Net observations report
  64. GRB230628E: VLT optical identification of afterglow candidate
  65. Fermi GRB 230628D: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S230628ax: Identification of a GW compact binary merger candidate
  67. GRB 230628E: LCOGT Optical Upper Limit
  68. Swift GRB230628.93: Global MASTER-Net observations report
  69. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  70. GRB 230628D: Fermi GBM Final Real-time Localization
  71. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230628aj: one counterpart neutrino candidate from IceCube neutrino searches
  72. GRB 230628C: Fermi GBM Final Real-time Localization
  73. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  74. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  75. LIGO/Virgo/KAGRA S230516az: GOTO candidate counterpart GOTO23hu ruled out by Zwicky Transient Facility observations
  76. ZTF23aaoohpy /AT2023lcr: TNG NIR detection
  77. GRB 230628A: Fermi GBM Final Localization
  78. LIGO/Virgo/KAGRA S230627c: Additional observations from the Zwicky Transient Facility
  79. GRB 230626A: GRBAlpha detection
  80. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  81. LIGO/Virgo/KAGRA S230627c: ATLAS information on the ZTF candidates
  82. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  83. GRB230626A: Fermi GBM Detection
  84. LIGO/Virgo/KAGRA S230627c: Global MASTER-Net observations report
  85. LIGO/Virgo/Kagra S230627c: NED Galaxies in the Localization Volume
  86. Konus-Wind detection of GRB 230616A
  87. LIGO/Virgo/KAGRA S230627c: Zwicky Transient Facility observations and candidates
  88. LIGO/Virgo/KAGRA S230627c: Coverage and upper limits from MAXI/GSC observations
  89. LIGO/Virgo/KAGRA S230627c: Updated Sky localization and EM Bright Classification
  90. LIGO/Virgo/KAGRA S230627c: Identification of a GW compact binary merger candidate
  91. GRB 230618A: Swift-BAT refined analysis
  92. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  93. LIGO/Virgo/KAGRA S230624av: Updated Sky localization
  94. GRB 230622A: Swift-BAT refined analysis
  95. GRB 230623A: Swift-XRT observations
  96. GRB 230625A: Fermi GBM Final Real-time Localization
  97. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  98. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  99. LIGO/Virgo/KAGRA S230624av: Identification of a GW compact binary merger candidate
  100. IceCube-Cascade 230622A: Upper limits from a search for additional neutrino events in IceCube

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