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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"

32714 results found.

  1. GRB 241204A: COLIBRÍ Optical Upper Limit
  2. EP241202b: KAIT optical upper limit
  3. GRB 241204A: DDOTI Upper Limits on the Afterglow
  4. GRB 241204A: Fermi GBM Observation
  5. Fermi GRB 241204A: Global MASTER-Net observations report
  6. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  7. GRB 241128A : RAPAS follow-up observations
  8. GRB 241201A: GRBAlpha detection
  9. EP241202b: Upper limits from Fermi-GBM Observations
  10. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  11. EP241202b: Kinder optical counterpart candidate
  12. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  13. GRB 241113B : RAPAS follow-up observation
  14. EP241201a: EP-FXT follow-up observations
  15. Konus-Wind detection of GRB 241130A
  16. EP241202b: Global MASTER-Net observations report
  17. EP241201a: BOOTES-5 optical upper limit
  18. EP241201a: NOT optical observations
  19. IPN triangulation of GRB 241130A
  20. GRB 241130A: EIRSAT-1 GMOD Detection
  21. GRB 241128A: Swift/UVOT Upper Limits
  22. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  23. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  24. EP241201a: Kinder optical counterpart candidate
  25. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  26. EP241201a: Global MASTER-Net observations report
  27. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  28. EP241126a: SOAR observations of the optical counterpart
  29. Fermi GRB 241201A: Global MASTER-Net observations report
  30. EP241126a: 1.6m Mephisto Optical Upper Limits
  31. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  32. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  33. IPN triangulation of GRB 241128B
  34. Konus-Wind detection of GRB 241114B
  35. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  36. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  37. GRB 241128A: AbAO optical upper limit
  38. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  39. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  40. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  41. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  42. GRB 241128A: Swift-BAT refined analysis
  43. GRB 241127A: Swift-BAT refined analysis
  44. EP241126a: NOT optical observations
  45. GRB 241127A: PRIME near-infrared detection
  46. GRB 241128A: Mondy optical observations
  47. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  48. Swift-XRT observations of IceCube -241127A
  49. Swift GRB 241128A: Global MASTER-Net observations report
  50. Fermi-LAT gamma-ray observations of IceCube-241127A
  51. EP241126a: SVOM/VT observations
  52. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  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. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  58. GRB 241127A: Swift/UVOT Detection
  59. GRB 241127A: SVOM/GRM observation
  60. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  61. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  62. EP241126a: WFST Observations
  63. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  64. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  65. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  66. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  67. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  68. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  69. EP241126a: Optical Upper limits with Kinder observations
  70. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  71. IPN triangulation of GRB 241114B
  72. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  73. EP241126a: EP-FXT follow-up observation update
  74. EP241126a: GSP detects optical counterpart
  75. EP241126a: TRT optical counterpart detection
  76. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  77. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  78. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  79. Trigger_18947: Swift ToO observations (retracted)
  80. GRB 241113B: EP-FXT afterglow detection
  81. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  82. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  83. SVOM/GRM detection of a short burst from SGR 1830
  84. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  85. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  86. Konus-Wind detection of GRB 241115D / EP 241115a
  87. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  88. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  89. GRB 241026A: radio detection with the VLA
  90. EP241125a: Optical upper limit with Kinder observations
  91. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  92. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  93. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  94. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  95. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  96. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  97. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  98. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  99. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  100. GRB 241120A: GRBAlpha detection

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