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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').
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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"

12170 results found.

  1. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  2. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  3. GRB 241207C: MAXI/GSC detection
  4. GRB 241207B: Fermi GBM Final Real-time Localization
  5. Fermi GRB 241207A: Global MASTER-Net observations report
  6. EP241206a: Global MASTER-Net observations report
  7. EP241206a: EP detection of a fast X-ray transient
  8. GRB 241206A: Fermi GBM observation
  9. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  10. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  11. Fermi GRB 241206A: Global MASTER-Net observations report
  12. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  13. GRB 241204A: Fermi-LAT detection
  14. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  15. Konus-Wind detection of GRB 241130A
  16. EP241201a: BOOTES-5 optical upper limit
  17. EP241202b: EP detection of a fast X-ray transient
  18. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  19. EP241201a: Global MASTER-Net observations report
  20. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  21. Fermi trigger No 754701230: Global MASTER-Net observations report
  22. Konus-Wind detection of GRB 241114B
  23. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  24. Fermi-LAT gamma-ray observations of IceCube-241127A
  25. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  26. GRB 241128A: Swift-XRT refined Analysis
  27. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  28. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  29. GRB 241127A: Swift-XRT refined Analysis
  30. GRB 241127A: Swift detection of a burst with an optical counterpart
  31. Swift GRB241127.91: Global MASTER-Net observations report
  32. Swift GRB241127.91: Global MASTER-Net OT detection
  33. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  34. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  35. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  36. EP241126a: EP-FXT follow-up observation update
  37. EP241126a: EP detection of a fast X-ray transient
  38. SVOM/GRM detection of a short burst from SGR 1830
  39. GECAM detection of a short burst from SGR 1830
  40. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  41. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  42. Konus-Wind detection of GRB 241115D / EP 241115a
  43. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  44. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  45. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  46. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  47. GRB 241120A: GRBAlpha detection
  48. Konus-Wind detection of GRB 241117A
  49. GRB 241105A: ATCA radio detection
  50. Konus-Wind detection of GRB 241120A
  51. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 241120A: Mondy and AbAO optical observations
  53. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  54. EP241119a: GIT optical upper limits
  55. GRB 241120A: Fermi GBM Observation
  56. Integral GRB241120.25: Global MASTER-Net observations report
  57. EP241119a: Global MASTER-Net observations report
  58. EP241119a: EP detection of a fast X-ray transient
  59. GRB241120A: a long GRB detected by INTEGRAL
  60. GRB 241120A: Fermi GBM Final Real-time Localization
  61. GRB 241119A: Fermi GBM Final Real-time Localization
  62. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  63. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  64. Fermi GRB 241118A: Global MASTER-Net observations report
  65. Fermi GRB 241117B: Global MASTER-Net observations report
  66. GRB 241117B: Fermi GBM Final Real-time Localization
  67. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  68. Fermi GRB 241117A: Global MASTER-Net observations report
  69. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  70. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  71. EP241115a: EP detection of a fast X-ray transient
  72. GRB 241115A: Swift detection of a burst
  73. EP 241113a: LBT possible optical counterpart
  74. GRB 241113B: KAIT Optical Afterglow Candidate
  75. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  76. GRB 241030A: LCO optical observation
  77. EP241113b: Global MASTER-Net observations report
  78. Fermi-LAT gamma-ray observations of IceCube-241113A
  79. GRB 241113A: Swift-XRT refined Analysis
  80. Konus-Wind detection of GRB 241107A (short/hard)
  81. GRB 241112B: GMG Optical Upper Limit
  82. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  83. SVOM/GRM detection of a short burst from SGR 1E1841-045
  84. Fermi trigger No 753166198: Global MASTER-Net observations report
  85. GRB 241107A: GROWTH-India telescope optical upper limit
  86. GRB 241112B: Swift-XRT afterglow detection
  87. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  88. GRB 241107A: INTEGRAL IBIS localization
  89. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  90. GRB 241018A: cubesat Avion detection
  91. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  92. Fermi trigger No 752878030: Global MASTER-Net observations report
  93. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  94. INTEGRAL detection of a burst from 1E 1841-045
  95. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  96. EP241109a: confirmation of a stellar flare by BOOTES-7
  97. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  98. EP241107a: AKO Optical Afterglow Follow-Up Observations
  99. EP241107a: AKO Optical Afterglow Detection
  100. Konus-Wind detection of GRB 241105A (short with extended emission)

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