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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"

39155 results found.

  1. GRB 241206B: GWAC-F50A optical upper limit
  2. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  3. Fermi GRB 241206A: Global MASTER-Net observations report
  4. GRB 241206A: Fermi GBM Final Real-time Localization
  5. EP241201a: 1.6m Mephisto Optical Upper Limits
  6. GRB 241204A: COLIBRÍ Optical Upper Limit
  7. EP241202b: KAIT optical upper limit
  8. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  9. GRB 241204A: DDOTI Upper Limits on the Afterglow
  10. GRB 241204A: Fermi GBM Observation
  11. Fermi GRB 241204A: Global MASTER-Net observations report
  12. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  13. GRB 241128A : RAPAS follow-up observations
  14. GRB 241201A: GRBAlpha detection
  15. GRB 241204A: Fermi-LAT detection
  16. EP241202b: Upper limits from Fermi-GBM Observations
  17. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  18. GRB 241113B : RAPAS follow-up observation
  19. Konus-Wind detection of GRB 241130A
  20. EP241202b: Global MASTER-Net observations report
  21. IPN triangulation of GRB 241130A
  22. GRB 241130A: EIRSAT-1 GMOD Detection
  23. GRB 241128A: Swift/UVOT Upper Limits
  24. GRB 241130A: Fermi GBM Detection
  25. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  26. EP241201a: Kinder optical counterpart candidate
  27. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  28. EP241201a: Global MASTER-Net observations report
  29. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  30. GRB241201B: Fermi GBM Final Localization
  31. GRB241201B: Fermi GBM Final Localization
  32. Fermi GRB 241201A: Global MASTER-Net observations report
  33. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  34. GRB 241130A: Fermi GBM Final Real-time Localization
  35. GRB 241130A: Fermi GBM Final Real-time Localization
  36. EP241126a: 1.6m Mephisto Optical Upper Limits
  37. GRB 241201A: Fermi GBM Final Real-time Localization
  38. Fermi trigger No 754701230: Global MASTER-Net observations report
  39. IPN triangulation of GRB 241128B
  40. Konus-Wind detection of GRB 241114B
  41. GRB 241128A: AbAO optical upper limit
  42. GRB 241128C: SVOM/GRM observation
  43. GRB 241128B: SVOM/GRM observation
  44. GRB 241128A: Swift-BAT refined analysis
  45. GRB 241127A: Swift-BAT refined analysis
  46. GRB 241127A: PRIME near-infrared detection
  47. GRB 241128A: Mondy optical observations
  48. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  49. Swift GRB 241128A: Global MASTER-Net observations report
  50. GRB 241128A: Swift-XRT refined Analysis
  51. GRB 241129A: Fermi GBM Final Real-time Localization
  52. GRB 241128A: Enhanced Swift-XRT position
  53. GRB 241128A: NOT optical observations
  54. GRB 241128A: LCO optical detection
  55. GRB 241128A: 1.5m OSN optical afterglow detection
  56. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  57. Fermi trigger No 754492985: Global MASTER-Net observations report
  58. GRB 241128A: Swift-XRT afterglow detection
  59. GRB 241128A: Swift detection of a burst
  60. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  61. GRB 241127A: Swift/UVOT Detection
  62. GRB 241127A: Swift-XRT refined Analysis
  63. GRB 241127A: SVOM/GRM observation
  64. GRB 241127A: Enhanced Swift-XRT position
  65. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  66. Swift GRB241127.91: Global MASTER-Net OT detection
  67. IceCube Alert 241127.59: Global MASTER-Net observations report
  68. GRB 241127A: Swift detection of a burst with an optical counterpart
  69. Swift GRB241127.91: Global MASTER-Net observations report
  70. Swift GRB241127.91: Global MASTER-Net OT detection
  71. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  72. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  73. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  74. GRB 241126A: SVOM/GRM observation
  75. IPN triangulation of GRB 241114B
  76. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  77. EP241126a: GSP detects optical counterpart
  78. EP241126a: TRT optical counterpart detection
  79. GRB 241113B: EP-FXT afterglow detection
  80. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  81. SVOM/GRM detection of a short burst from SGR 1830
  82. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  83. Konus-Wind detection of GRB 241115D / EP 241115a
  84. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  85. GRB 241026A: radio detection with the VLA
  86. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  87. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  88. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  89. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  90. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  91. GRB 241120A: GRBAlpha detection
  92. GRB 241113B: SVOM/VT optical afterglow observations
  93. Konus-Wind detection of GRB 241117A
  94. GRB 241105A: ATCA radio detection
  95. IPN triangulation of GRB 241117A
  96. GRB 241026A: VIRT Optical Upper Limit
  97. GRB 241025A: VIRT Optical Upper Limit
  98. Konus-Wind detection of GRB 241120A
  99. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  100. EP241021a and EP241026b: Keck/LRIS spectroscopic observations

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