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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"

32551 results found.

  1. EP240919a: NOT and Gemini optical observations
  2. EP240919a: GOTO optical upper limits
  3. EP240919a: JinShan optical upper limits
  4. EP240919a is likely a GRB event (duplicate submission of 37563)
  5. EP240919a is likely a GRB event
  6. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  7. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  8. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  9. GRB 240918B: Fermi GBM Detection
  10. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  11. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  12. EP240918a: EP observation update
  13. GRB 240910A: further Swift observations and confirmation of afterglow
  14. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  15. EP240918a: Swift-XRT observation
  16. Fermi GRB 240918A: Global MASTER-Net observations report
  17. EP EP240918a: Global MASTER-Net observations report
  18. EP240918a: JinShan optical upper limits
  19. EP240918a: YAHPT Optical Upper Limit
  20. EP240918a: Optical upper limits with Kinder observations
  21. EP240918a: GMG Optical Upper Limit
  22. GRB 240916A: GRBAlpha detection
  23. GRB 240914B: GRBAlpha detection
  24. GRB 240916A: NOT optical observation
  25. GRB 240912A: Swift-BAT refined analysis
  26. IPN triangulation of GRB 240913C / EP 240913a
  27. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  28. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  29. GRB 240916A: Fermi GBM Observation
  30. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  31. GRB 240821A: radio observation with the VLA
  32. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  33. GRB 240916A: Swift-XRT afterglow detection
  34. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  35. GRB 240916A: Swift ToO observations
  36. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  37. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  38. EP EP240913a: Global MASTER-Net observations report
  39. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  40. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  41. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  42. EP240913a: VLT/HAWK-I near-infrared upper limits
  43. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  44. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  45. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  46. EP240913a/GRB 240913C: KAIT optical upper limit
  47. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  48. GRB 240913C: Fermi GBM detection
  49. GRB 240913C: Joint location by ETJASMIN
  50. GRB 240914B: AstroSat CZTI detection
  51. EP240913A / GRB 240913C: AstroSat CZTI detection
  52. GRB 240914A: SVOM/GRM observation
  53. GRB 240910A: SVOM/VT optical observations
  54. GRB 240914A: Swift ToO observations
  55. EP240913a: NOT optical upper limits
  56. EP240913a: JinShan optical upper limits
  57. EP240913a: ESO-NTT optical observations
  58. GRB 240914A: ESO-NTT optical observations
  59. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  60. GRB 240905E: further NOT optical observations
  61. EP240913a: A GRB Event
  62. GRB 240911A: LCO optical observations
  63. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  64. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  65. GRB 240912A: Swift/UVOT Detection
  66. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  67. GRB 240912A: SVOM/GRM observation
  68. Fermi GRB 240913A: Global MASTER-Net observations report
  69. GRB 240912A: J-band observations with WINTER
  70. GRB 240912A: Fermi GBM Observation
  71. Swift GRB 240912A: Global MASTER-Net observations report
  72. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  73. GRB 240911A: Tiled Swift observations
  74. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  75. GRB 240912A: NOT optical spectroscopy
  76. GRB 240912A: Redshift from OSIRIS+/GTC
  77. Fast X-ray Transient EP240801a: GMRT radio observations
  78. GRB 240910A: Redshift from OSIRIS+/GTC
  79. GRB 240910A: Fermi GBM Observation
  80. GRB 240910A: NOT optical observations
  81. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  82. GRB 240910A: JinShan optical observations
  83. GRB 240910A: GOTO candidate optical counterpart
  84. EP240908a: Optical afterglow confirmation
  85. GRB 240710A: SVOM/GRM observation
  86. GRB 240910A: Swift ToO observations
  87. IPN triangulation of GRB 240905B (short)
  88. GRB 240825A: 7DT Optical Upper Limit
  89. GRB 240905E: SVOM/VT optical observations
  90. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  91. GRB 240910A: GRBAlpha detection
  92. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  93. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  94. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  95. GRB 240910A: SVOM/GRM observation
  96. EP240908a: Mondy and AbAO follow-up observations
  97. EP240908a: Updates on the WXT detection result around the trigger time
  98. Fermi GRB 240910A: Global MASTER-Net observations report
  99. EP240908a: optical afterglow candidate
  100. EP EP240908a: Global MASTER-Net observations report

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