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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"

21043 results found.

  1. EP240918a: EP observation update
  2. GRB 240910A: further Swift observations and confirmation of afterglow
  3. Fermi GRB 240918A: Global MASTER-Net observations report
  4. EP EP240918a: Global MASTER-Net observations report
  5. EP240918a: JinShan optical upper limits
  6. EP240918a: Optical upper limits with Kinder observations
  7. EP240918a: an X-ray transient detected by Einstein Probe
  8. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  9. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  10. GRB 240821A: radio observation with the VLA
  11. GRB 240916A: Swift-XRT afterglow detection
  12. GRB 240916A: Swift ToO observations
  13. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  14. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  15. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  16. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  17. EP EP240913a: Global MASTER-Net observations report
  18. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  19. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  20. EP240913a: VLT/HAWK-I near-infrared upper limits
  21. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  22. GRB 240914A: Swift-XRT observations
  23. GRB 240910A: SVOM/VT optical observations
  24. GRB 240914A: Swift ToO observations
  25. EP240913a: NOT optical upper limits
  26. EP240913a: JinShan optical upper limits
  27. EP240913a: ESO-NTT optical observations
  28. GRB 240914A: ESO-NTT optical observations
  29. GRB 240905E: further NOT optical observations
  30. EP240913a: A GRB Event
  31. EP240913a: EP-WXT detection of a fast X-ray transient
  32. GRB 240911A: LCO optical observations
  33. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  34. GRB 240912A: Swift/UVOT Detection
  35. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  36. Fermi trigger No 747920561: Global MASTER-Net observations report
  37. GRB 240911A: Swift-XRT observations
  38. Fermi GRB 240913A: Global MASTER-Net observations report
  39. GRB 240912A: J-band observations with WINTER
  40. Swift GRB 240912A: Global MASTER-Net observations report
  41. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  42. GRB 240911A: Tiled Swift observations
  43. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  44. GRB 240912A: Redshift from OSIRIS+/GTC
  45. Fast X-ray Transient EP240801a: GMRT radio observations
  46. GRB 240910A: NOT optical observations
  47. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  48. GRB 240910A: JinShan optical observations
  49. GRB 240910A: GOTO candidate optical counterpart
  50. EP240908a: Optical afterglow confirmation
  51. GRB 240910A: Swift ToO observations
  52. GRB 240825A: 7DT Optical Upper Limit
  53. GRB 240905E: SVOM/VT optical observations
  54. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  55. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  56. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  57. EP240908a: Mondy and AbAO follow-up observations
  58. EP240908a: Updates on the WXT detection result around the trigger time
  59. Fermi GRB 240910A: Global MASTER-Net observations report
  60. EP240908a: optical afterglow candidate
  61. EP EP240908a: Global MASTER-Net observations report
  62. Fermi trigger No 747553301: Global MASTER-Net observations report
  63. EP240908a: TRT optical upper limit
  64. GRB 240905B: GOTO optical upper limits
  65. EP240908a: EP detection of a fast X-ray transient
  66. Fermi GRB 240908A: Global MASTER-Net observations report
  67. GRB 240905E: GIT optical upper limit
  68. GRB 240905B: Swift-XRT observations
  69. GRB 240905E: Gaoyazi/GOT optical upper limits
  70. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  71. GRB 240905B: Swift ToO observations
  72. GRB 240905E: J-band observations with WINTER
  73. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  74. Fermi GRB 240905D: Global MASTER-Net observations report
  75. Fermi GRB 240905A: Global MASTER-Net observations report
  76. GRB 240905E: REM optical/NIR upper limits
  77. GRB 240905E: Swift/UVOT Upper Limits
  78. GRB 240905E: SAO RAS optical upper limit
  79. GRB 240825A: Montarrenti Observatory optical follow-up observations
  80. GRB 240905E: Nanshan/HMT optical upper limit
  81. Swift GRB 240905E: Global MASTER-Net observations report
  82. Fermi GRB 240905B: Global MASTER-Net observations report
  83. GRB 240825A: ATCA Detection of Radio Counterpart
  84. Swift GRB 240904A: Global MASTER-Net observations report
  85. Fermi trigger No 747163821: Global MASTER-Net observations report
  86. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  87. GRB 240825A: MeerLICHT afterglow detection
  88. Fermi trigger No 746923430: Global MASTER-Net observations report
  89. GRB 240828A: SAO RAS AS-500(2) optical observations
  90. GRB 240821A: VLT spectroscopic observations
  91. Fermi trigger No 746882332: Global MASTER-Net observations report
  92. GRB240828B: REM optical/NIR upper limits
  93. Fermi trigger No 746816563: Global MASTER-Net observations report
  94. GRB 240825A: SOAR observations
  95. GRB 240828B: Mephisto optical upper limit
  96. GRB 240828B: GRANDMA Optical Upper Limit
  97. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  98. GRB 240825A: MeerKAT detection
  99. GRB 240828B: J-band upper limit from WINTER
  100. Fermi trigger No 746684112: Global MASTER-Net observations report

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