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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"

21952 results found.

  1. GRB 240828B: Swift-XRT afterglow detection
  2. GRB 240828A: AstroSat CZTI detection of a long burst
  3. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  4. GRB 240825A: Upper limits from a neutrino search with IceCube
  5. GRB 240819A as a likely X-Ray Flash
  6. GRB 240821A: PRIME near-infrared observations
  7. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  8. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  9. GRB 240825A: SAO RAS optical observations
  10. GRB 240824A: GIT optical upper limit
  11. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  12. GRB 240825A: GMG Continued Optical Observation on the Second Night
  13. GRB 240825A: PRIME near-infrared detection
  14. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  15. GRB 240825A: AKO Optical Follow-Up Observations
  16. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  17. GRB 240825A: Swift/UVOT Detection
  18. GRB 240825A: REM detection of the optical/NIR afterglow
  19. GRB 240825A: Montarrenti Observatory optical observations
  20. GRB 240825A: Enhanced Swift-XRT position
  21. GRB 240825A: Fermi-LAT detection
  22. GRB 240825A: LCO optical observations
  23. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  24. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  25. GRB 240824B: NOT optical upper limit
  26. GRB 240825A: GMG Optical Observation
  27. GRB 240825A: 1.6m Mephisto multi-band detection
  28. GRB 240825A: AKO Optical Afterglow Detection
  29. GRB 240825A: Skynet Optical Afterglow observations
  30. GRB 240825A: Nanshan/HMT optical afterglow observations
  31. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  32. GRB 240824A: SVOM/C-GFT optical upper limit
  33. GRB 240824B: Swift-XRT afterglow detection
  34. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  35. GRB 240824A: Swift/UVOT Upper Limits
  36. GRB 240821A: Swift/UVOT observations of the XRT sources.
  37. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  38. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  39. GRB 240824A: KAIT optical upper limit
  40. GRB 240824A: Skynet Optical Afterglow Discovery
  41. GRB 240824A: Swift detection of a burst
  42. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  43. GRB 240821A: Colibri Optical Upper Limit
  44. EP240820a: PRIME J-band Observations
  45. GRB 240821A: REM optical/NIR upper limits
  46. GRB 240821A: LCO optical observations
  47. GRB 240821A: JinShan optical upper limits
  48. GRB 240809A: Mondy and AbAO Optical Observations
  49. GRB 240821A: GMG Optical Upper Limit
  50. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  51. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  52. EP240820a: TRT optical upper limit
  53. EP240820a: EP detection of a fast X-ray transient
  54. EP240816a: PRIME upper limits
  55. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  56. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  57. EP240816b: Liverpool Telescope optical follow-up observations
  58. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  59. GRB 240814B: GRBAlpha detection
  60. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  61. EP240816b: TRT optical upper limit
  62. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  63. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  64. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  66. EP240807a: PRIME H-band upper limits
  67. GRB 240811A: Bassano Bresciano Observatory upper limit
  68. GRB 240811A: Swift/UVOT Upper Limits
  69. EP240801a: Assy-Turgen optical observations
  70. GRB 240811A: LCOGT Optical Upper Limit
  71. GRB 240811A: Enhanced Swift-XRT position
  72. GRB 240811A: Upper limits with Mephisto
  73. Konus-Wind detection of GRB 240809A
  74. GRB 240811A: Swift detection of a burst
  75. GRB 240809A: REM detection of the optical afterglow
  76. GRB 240809A: Bassano Bresciano Observatory optical observations
  77. GRB 240809A: GIT afterglow observations
  78. GRB 240809A: Swift/UVOT Detection
  79. IPN triangulation of GRB 240807A / EP 240807a
  80. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  81. X-ray Transient EP240807a: PRIME near-infrared upper limits
  82. GRB 240809A: JinShan optical observations
  83. GRB 240809A: Enhanced Swift-XRT position
  84. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  85. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  86. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  87. GRB 240801A: GRBAlpha detection
  88. GRB 240710B: VZLUSAT-2 detection
  89. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  90. S240807h: Identification of a GW compact binary merger candidate
  91. GRB 240720B: VZLUSAT-2 detection
  92. GRB 240710A: VZLUSAT-2 detection
  93. EP240806A: Liverpool Telescope optical follow-up observations
  94. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  95. EP240807a: EP-WXT detection of a fast X-ray transient
  96. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  97. GRB 240805B: GIT optical upper limit
  98. EP240806a: LCOGT optical counterpart detection
  99. Konus-Wind detection of GRB 240802A (EP240802a)
  100. Konus-Wind detection of GRB 240805A

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