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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"

32720 results found.

  1. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  2. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  3. GRB 241206B: GWAC-F50A optical upper limit
  4. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  5. Fermi GRB 241206A: Global MASTER-Net observations report
  6. EP241201a: 1.6m Mephisto Optical Upper Limits
  7. GRB 241204A: COLIBRÍ Optical Upper Limit
  8. EP241202b: KAIT optical upper limit
  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. EP241202b: Upper limits from Fermi-GBM Observations
  16. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  17. EP241202b: Kinder optical counterpart candidate
  18. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  19. GRB 241113B : RAPAS follow-up observation
  20. EP241201a: EP-FXT follow-up observations
  21. Konus-Wind detection of GRB 241130A
  22. EP241202b: Global MASTER-Net observations report
  23. EP241201a: BOOTES-5 optical upper limit
  24. EP241201a: NOT optical observations
  25. IPN triangulation of GRB 241130A
  26. GRB 241130A: EIRSAT-1 GMOD Detection
  27. GRB 241128A: Swift/UVOT Upper Limits
  28. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  29. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  30. EP241201a: Kinder optical counterpart candidate
  31. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  32. EP241201a: Global MASTER-Net observations report
  33. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  34. EP241126a: SOAR observations of the optical counterpart
  35. Fermi GRB 241201A: Global MASTER-Net observations report
  36. EP241126a: 1.6m Mephisto Optical Upper Limits
  37. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  38. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  39. IPN triangulation of GRB 241128B
  40. Konus-Wind detection of GRB 241114B
  41. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  42. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  43. GRB 241128A: AbAO optical upper limit
  44. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  45. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  46. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  47. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  48. GRB 241128A: Swift-BAT refined analysis
  49. GRB 241127A: Swift-BAT refined analysis
  50. EP241126a: NOT optical observations
  51. GRB 241127A: PRIME near-infrared detection
  52. GRB 241128A: Mondy optical observations
  53. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  54. Swift-XRT observations of IceCube -241127A
  55. Swift GRB 241128A: Global MASTER-Net observations report
  56. Fermi-LAT gamma-ray observations of IceCube-241127A
  57. EP241126a: SVOM/VT observations
  58. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  59. GRB 241128A: NOT optical observations
  60. GRB 241128A: LCO optical detection
  61. GRB 241128A: 1.5m OSN optical afterglow detection
  62. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  63. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  64. GRB 241127A: Swift/UVOT Detection
  65. GRB 241127A: SVOM/GRM observation
  66. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  67. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  68. EP241126a: WFST Observations
  69. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  70. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  71. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  72. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  73. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  74. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  75. EP241126a: Optical Upper limits with Kinder observations
  76. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  77. IPN triangulation of GRB 241114B
  78. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  79. EP241126a: EP-FXT follow-up observation update
  80. EP241126a: GSP detects optical counterpart
  81. EP241126a: TRT optical counterpart detection
  82. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  83. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  84. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  85. Trigger_18947: Swift ToO observations (retracted)
  86. GRB 241113B: EP-FXT afterglow detection
  87. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  88. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  89. SVOM/GRM detection of a short burst from SGR 1830
  90. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  91. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  92. Konus-Wind detection of GRB 241115D / EP 241115a
  93. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  94. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  95. GRB 241026A: radio detection with the VLA
  96. EP241125a: Optical upper limit with Kinder observations
  97. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  98. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  99. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  100. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region

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