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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

23614 results found.

  1. GRB 240825A: LCO optical observations
  2. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  3. GRB 240824B: Fermi GBM Observation
  4. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  5. GRB 240824B: NOT optical upper limit
  6. GRB 240825A: GMG Optical Observation
  7. GRB 240825A: 1.6m Mephisto multi-band detection
  8. GRB 240825A: AKO Optical Afterglow Detection
  9. GRB 240825A: Skynet Optical Afterglow observations
  10. GRB 240825A: Nanshan/HMT optical afterglow observations
  11. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  12. GRB 240824A: SVOM/C-GFT optical upper limit
  13. GRB 240824B: Swift-XRT afterglow detection
  14. GRB 240824A: Swift-XRT observations
  15. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  16. GRB 240824B: Swift/BAT arcminute localization of a burst
  17. GRB 240824A: Swift/UVOT Upper Limits
  18. GRB 240821A: Swift/UVOT observations of the XRT sources.
  19. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  20. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  21. GRB 240824A: Skynet Optical Afterglow Discovery
  22. GRB 240824A: Swift detection of a burst
  23. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  24. GRB 240821A: Colibri Optical Upper Limit
  25. EP240820a: PRIME J-band Observations
  26. GRB 240821A: Swift-XRT observations
  27. GRB 240821A: REM optical/NIR upper limits
  28. GRB 240821A: LCO optical observations
  29. GRB 240821A: JinShan optical upper limits
  30. GRB 240809A: Mondy and AbAO Optical Observations
  31. GRB 240821A: GMG Optical Upper Limit
  32. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  33. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  34. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  35. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  36. GRB 240819A: Swift-XRT observations
  37. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  38. EP240820a: TRT optical upper limit
  39. EP240820a: EP detection of a fast X-ray transient
  40. EP240816a: PRIME upper limits
  41. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  42. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  43. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  44. GRB 240819A: X-ray follow-up observation with EP-FXT
  45. EP240816b: Liverpool Telescope optical follow-up observations
  46. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  47. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  48. EP240816b: TRT optical upper limit
  49. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  50. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  51. Konus-Wind detection of GRB 240810A
  52. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  53. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  54. GRB 240809A: ATA radio non-detection
  55. GRB 240809A : RAPAS follow-up observations
  56. IPN triangulation of GRB 240810A (short)
  57. EP240807a: PRIME H-band upper limits
  58. GRB 240812B: AstroSat CZTI detection of a long burst
  59. GRB 240811A: Bassano Bresciano Observatory upper limit
  60. GRB 240811A: Swift/UVOT Upper Limits
  61. EP240801a: Assy-Turgen optical observations
  62. GRB 240811A: LCOGT Optical Upper Limit
  63. GRB 240811A: Enhanced Swift-XRT position
  64. GRB 240811A: Upper limits with Mephisto
  65. GRB 240811A: Swift detection of a burst
  66. GRB 240809A: REM detection of the optical afterglow
  67. GRB 240809A: Bassano Bresciano Observatory optical observations
  68. GRB 240808A: AstroSat CZTI detection
  69. GRB 240809A: GIT afterglow observations
  70. GRB 240809A: Swift/UVOT Detection
  71. IPN triangulation of GRB 240807A / EP 240807a
  72. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  73. X-ray Transient EP240807a: PRIME near-infrared upper limits
  74. GRB 240809A: JinShan optical observations
  75. GRB 240809A: Enhanced Swift-XRT position
  76. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  77. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  78. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  79. EP240807a: STEP/T80S optical limits
  80. GRB 240805A: ATCA Radio Upper Limits
  81. S240807h: Identification of a GW compact binary merger candidate
  82. EP240806A: Liverpool Telescope optical follow-up observations
  83. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  84. EP240807a: EP-WXT detection of a fast X-ray transient
  85. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  86. GRB 240805B: GIT optical upper limit
  87. EP240806a: LCOGT optical counterpart detection
  88. Konus-Wind detection of GRB 240802A (EP240802a)
  89. Improved IPN triangulation of GRB 240802A / EP 240802a
  90. GRB 240805B Bassano Bresciano Observatory upper limit
  91. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  92. EP 240806A: LCO optical observations
  93. EP240806a: EP-WXT detection of a fast X-ray transient
  94. GRB 240805B: Optical detection with 1.6m Mephisto
  95. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  96. GRB 240805B: Swift-XRT refined Analysis
  97. GRB 240805B: Swift/UVOT Upper Limits
  98. GRB 240805A: Swift/UVOT Upper Limits
  99. GRB 240805B: BTA optical afterglow candidate
  100. GRB 240805B: Enhanced Swift-XRT position

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