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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"

32718 results found.

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

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