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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

11757 results found.

  1. EP241208a: EP-FXT follow-up observations
  2. Fermi trigger No 755485387: Global MASTER-Net observations report
  3. GRB 241207B: Fermi GBM Observation
  4. GRB 241209D: Swift-XRT refined Analysis
  5. GRB 241209D: COLIBRÍ detection of the afterglow
  6. Fermi GRB 241209D: Global MASTER-Net observations report
  7. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  8. Swift GRB 241209D: Global MASTER-Net observations report
  9. Fermi GRB 241209A: Global MASTER-Net observations report
  10. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  11. EP241208a: EP detection of a fast X-ray transient
  12. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  13. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  14. GRB 241207C: MAXI/GSC detection
  15. GRB 241207B: Fermi GBM Final Real-time Localization
  16. Fermi GRB 241207A: Global MASTER-Net observations report
  17. EP241206a: Global MASTER-Net observations report
  18. EP241206a: EP detection of a fast X-ray transient
  19. GRB 241206A: Fermi GBM observation
  20. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  21. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  22. Fermi GRB 241206A: Global MASTER-Net observations report
  23. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  24. GRB 241204A: Fermi-LAT detection
  25. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  26. Konus-Wind detection of GRB 241130A
  27. EP241201a: BOOTES-5 optical upper limit
  28. EP241202b: EP detection of a fast X-ray transient
  29. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  30. EP241201a: Global MASTER-Net observations report
  31. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  32. Fermi trigger No 754701230: Global MASTER-Net observations report
  33. Konus-Wind detection of GRB 241114B
  34. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  35. Fermi-LAT gamma-ray observations of IceCube-241127A
  36. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  37. GRB 241128A: Swift-XRT refined Analysis
  38. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  39. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  40. GRB 241127A: Swift-XRT refined Analysis
  41. GRB 241127A: Swift detection of a burst with an optical counterpart
  42. Swift GRB241127.91: Global MASTER-Net observations report
  43. Swift GRB241127.91: Global MASTER-Net OT detection
  44. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  45. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  46. EP241126a: EP-FXT follow-up observation update
  47. EP241126a: EP detection of a fast X-ray transient
  48. GECAM detection of a short burst from SGR 1830
  49. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  50. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  51. Konus-Wind detection of GRB 241115D / EP 241115a
  52. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  53. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  54. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  55. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  56. GRB 241120A: GRBAlpha detection
  57. Konus-Wind detection of GRB 241117A
  58. GRB 241105A: ATCA radio detection
  59. Konus-Wind detection of GRB 241120A
  60. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 241120A: Mondy and AbAO optical observations
  62. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  63. EP241119a: GIT optical upper limits
  64. GRB 241120A: Fermi GBM Observation
  65. Integral GRB241120.25: Global MASTER-Net observations report
  66. EP241119a: Global MASTER-Net observations report
  67. EP241119a: EP detection of a fast X-ray transient
  68. GRB241120A: a long GRB detected by INTEGRAL
  69. GRB 241120A: Fermi GBM Final Real-time Localization
  70. GRB 241119A: Fermi GBM Final Real-time Localization
  71. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  72. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  73. Fermi GRB 241118A: Global MASTER-Net observations report
  74. Fermi GRB 241117B: Global MASTER-Net observations report
  75. GRB 241117B: Fermi GBM Final Real-time Localization
  76. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  77. Fermi GRB 241117A: Global MASTER-Net observations report
  78. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  79. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  80. EP241115a: EP detection of a fast X-ray transient
  81. GRB 241115A: Swift detection of a burst
  82. EP 241113a: LBT possible optical counterpart
  83. GRB 241113B: KAIT Optical Afterglow Candidate
  84. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  85. GRB 241030A: LCO optical observation
  86. EP241113b: Global MASTER-Net observations report
  87. Fermi-LAT gamma-ray observations of IceCube-241113A
  88. GRB 241113A: Swift-XRT refined Analysis
  89. Konus-Wind detection of GRB 241107A (short/hard)
  90. GRB 241112B: GMG Optical Upper Limit
  91. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  92. Fermi trigger No 753166198: Global MASTER-Net observations report
  93. GRB 241107A: GROWTH-India telescope optical upper limit
  94. GRB 241112B: Swift-XRT afterglow detection
  95. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  96. GRB 241107A: INTEGRAL IBIS localization
  97. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  98. GRB 241018A: cubesat Avion detection
  99. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  100. Fermi trigger No 752878030: Global MASTER-Net observations report

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