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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"

45727 results found.

  1. EP241206a: EP detection of a fast X-ray transient
  2. GRB 241206A: Fermi GBM observation
  3. GRB 241206C: SVOM/GRM observation of a likely short burst
  4. GRB 241207A: Fermi GBM Final Real-time Localization
  5. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  6. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  7. GRB 241206B: GWAC-F50A optical upper limit
  8. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  9. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  10. Fermi GRB 241206A: Global MASTER-Net observations report
  11. GRB 241206A: Fermi GBM Final Real-time Localization
  12. EP241201a: 1.6m Mephisto Optical Upper Limits
  13. GRB 241204A: COLIBRÍ Optical Upper Limit
  14. EP241202b: KAIT optical upper limit
  15. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  16. GRB 241204A: DDOTI Upper Limits on the Afterglow
  17. GRB 241204A: Fermi GBM Observation
  18. Fermi GRB 241204A: Global MASTER-Net observations report
  19. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  20. GRB 241128A : RAPAS follow-up observations
  21. GRB 241201A: GRBAlpha detection
  22. GRB 241204A: Fermi-LAT detection
  23. EP241202b: Upper limits from Fermi-GBM Observations
  24. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  25. EP241202b: Kinder optical counterpart candidate
  26. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  27. GRB 241113B : RAPAS follow-up observation
  28. EP241201a: EP-FXT follow-up observations
  29. Konus-Wind detection of GRB 241130A
  30. EP241202b: Global MASTER-Net observations report
  31. EP241201a: BOOTES-5 optical upper limit
  32. EP241202b: EP detection of a fast X-ray transient
  33. EP241201a: NOT optical observations
  34. IPN triangulation of GRB 241130A
  35. GRB 241130A: EIRSAT-1 GMOD Detection
  36. GRB 241128A: Swift/UVOT Upper Limits
  37. GRB 241130A: Fermi GBM Detection
  38. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  39. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  40. EP241201a: Kinder optical counterpart candidate
  41. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  42. EP241201a: Global MASTER-Net observations report
  43. EP241201a: EP detection of a fast X-ray transient
  44. The EP-WXT trigger 01709126243 is not a real source
  45. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  46. GRB241201B: Fermi GBM Final Localization
  47. GRB241201B: Fermi GBM Final Localization
  48. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  49. EP241126a: SOAR observations of the optical counterpart
  50. Fermi GRB 241201A: Global MASTER-Net observations report
  51. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  52. GRB 241130A: Fermi GBM Final Real-time Localization
  53. GRB 241130A: Fermi GBM Final Real-time Localization
  54. EP241126a: 1.6m Mephisto Optical Upper Limits
  55. GRB 241201A: Fermi GBM Final Real-time Localization
  56. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  58. Fermi trigger No 754701230: Global MASTER-Net observations report
  59. IPN triangulation of GRB 241128B
  60. Konus-Wind detection of GRB 241114B
  61. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  62. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  63. GRB 241128A: AbAO optical upper limit
  64. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  65. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  66. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  67. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  68. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  69. GRB 241128C: SVOM/GRM observation
  70. GRB 241128B: SVOM/GRM observation
  71. GRB 241128A: Swift-BAT refined analysis
  72. GRB 241127A: Swift-BAT refined analysis
  73. EP241126a: NOT optical observations
  74. GRB 241127A: PRIME near-infrared detection
  75. GRB 241128A: Mondy optical observations
  76. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  77. Swift-XRT observations of IceCube -241127A
  78. Swift GRB 241128A: Global MASTER-Net observations report
  79. Fermi-LAT gamma-ray observations of IceCube-241127A
  80. EP241126a: SVOM/VT observations
  81. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  82. GRB 241128A: Swift-XRT refined Analysis
  83. GRB 241129A: Fermi GBM Final Real-time Localization
  84. GRB 241128A: Enhanced Swift-XRT position
  85. GRB 241128A: NOT optical observations
  86. GRB 241128A: LCO optical detection
  87. GRB 241128A: 1.5m OSN optical afterglow detection
  88. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  89. Fermi trigger No 754492985: Global MASTER-Net observations report
  90. GRB 241128A: Swift-XRT afterglow detection
  91. GRB 241128A: Swift detection of a burst
  92. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  93. GRB 241127A: Swift/UVOT Detection
  94. GRB 241127A: Swift-XRT refined Analysis
  95. GRB 241127A: SVOM/GRM observation
  96. GRB 241127A: Enhanced Swift-XRT position
  97. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  98. The EP-WXT trigger 01709125191 is not a real source
  99. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  100. Swift GRB241127.91: Global MASTER-Net OT detection

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