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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"

28295 results found.

  1. GRB 240825A: 1.6m Mephisto multi-band detection
  2. GRB 240825A: AKO Optical Afterglow Detection
  3. GRB 240825A: Skynet Optical Afterglow observations
  4. GRB 240825A: Nanshan/HMT optical afterglow observations
  5. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  6. GRB 240824A: Swift-BAT refined analysis
  7. GRB 240824A: SVOM/C-GFT optical upper limit
  8. GRB 240824B: Swift-XRT afterglow detection
  9. GRB 240824A: Swift-XRT observations
  10. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  11. GRB 240824A: Swift/UVOT Upper Limits
  12. GRB 240821A: Swift/UVOT observations of the XRT sources.
  13. GRB 240824B: MAXI/GSC detection
  14. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  15. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  16. GRB 240824A: Skynet Optical Afterglow Discovery
  17. GRB 240824A: Swift detection of a burst
  18. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  19. GRB 240821A: Colibri Optical Upper Limit
  20. EP240820a: PRIME J-band Observations
  21. GRB 240821A: Swift-XRT observations
  22. GRB 240822A: AstroSat CZTI detection of a short burst
  23. GRB 240821A: REM optical/NIR upper limits
  24. GRB 240821A: LCO optical observations
  25. GRB 240821A: JinShan optical upper limits
  26. GRB 240809A: Mondy and AbAO Optical Observations
  27. GRB 240821A: GMG Optical Upper Limit
  28. Fermi GRB 240821A: Global MASTER-Net observations report
  29. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  30. GRB 240821A: Fermi GBM Observation
  31. Fermi trigger No 745925274: Global MASTER-Net observations report
  32. Fermi trigger No 745935375: Global MASTER-Net observations report
  33. GRB240821A: EIRSAT-1 GMOD Detection
  34. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  35. GRB 240821A: SVOM/GRM observation
  36. GRB 240821A: SVOM/GRM observation
  37. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  38. Fermi trigger No 745866488: Global MASTER-Net observations report
  39. GRB 240821A: BALROG localization (Fermi Trigger 745958167 / GRB 240821775)
  40. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  41. GRB 240819A: Swift-XRT observations
  42. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  43. EP240820a: TRT optical upper limit
  44. EP240820a: EP detection of a fast X-ray transient
  45. EP240816a: PRIME upper limits
  46. Fermi trigger No 745873283: Global MASTER-Net observations report
  47. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  48. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  49. EP240816b: Liverpool Telescope optical follow-up observations
  50. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  51. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  52. EP240816b: TRT optical upper limit
  53. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  54. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  55. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  56. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  58. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  59. GRB 240810A: SVOM/GRM observation
  60. GRB 240809A : RAPAS follow-up observations
  61. GRB 240811A: Swift-BAT refined analysis
  62. GRB 240809A: Swift-BAT refined analysis
  63. EP240807a: PRIME H-band upper limits
  64. IceCube-240808A: Upper limits from a search for additional neutrino events in IceCube
  65. GRB 240811A: Bassano Bresciano Observatory upper limit
  66. GRB 240811A: Swift-XRT refined Analysis
  67. GRB 240811A: Swift/UVOT Upper Limits
  68. EP240801a: Assy-Turgen optical observations
  69. Fermi GRB 240810A: Global MASTER-Net observations report
  70. GRB 240811A: LCOGT Optical Upper Limit
  71. GRB 240811A: Enhanced Swift-XRT position
  72. GRB 240811A: Upper limits with Mephisto
  73. GRB 240811A: Swift detection of a burst
  74. GRB 240809A: REM detection of the optical afterglow
  75. GRB 240809A: Bassano Bresciano Observatory optical observations
  76. Fermi-LAT gamma-ray observations of IceCube-240808A
  77. GRB 240809A: GIT afterglow observations
  78. GRB 240809B: MAXI/GSC detection
  79. GRB 240809A: Swift/UVOT Detection
  80. GRB 240809A: Swift-XRT refined Analysis
  81. IPN triangulation of GRB 240807A / EP 240807a
  82. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  83. X-ray Transient EP240807a: PRIME near-infrared upper limits
  84. GRB 240809A: JinShan optical observations
  85. GRB 240809A: Enhanced Swift-XRT position
  86. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  87. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  88. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  89. EP EP240806a: Global MASTER-Net observations report
  90. GRB 240710B: VZLUSAT-2 detection
  91. S240807h: Identification of a GW compact binary merger candidate
  92. GRB 240720B: VZLUSAT-2 detection
  93. GRB 240710A: VZLUSAT-2 detection
  94. EP240806A: Liverpool Telescope optical follow-up observations
  95. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  96. EP240807a: EP-WXT detection of a fast X-ray transient
  97. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  98. GRB 240805B: GIT optical upper limit
  99. GRB 240805B: Swift-BAT refined analysis
  100. GRB 240805A: Swift-BAT refined analysis

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