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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"

19689 results found.

  1. GRB 241209A: VLT optical observations
  2. GRB 241209A: GOTO optical upper limits
  3. EP241206a: 1.5m OSN optical limit
  4. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  5. EP241208a: EP detection of a fast X-ray transient
  6. GRB 241209A: Swift detection of a short burst
  7. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  8. GRB 241201A: AstroSat CZTI detection
  9. GRB 241206A: DDOTI Upper Limit on the Afterglow
  10. EP241206a: BOOTES Global Network optical limits
  11. GRB 241207C: Tiled Swift observations
  12. EP241206a: EP detection of a fast X-ray transient
  13. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  14. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  15. EP241201a: 1.6m Mephisto Optical Upper Limits
  16. GRB 241204A: COLIBRÍ Optical Upper Limit
  17. EP241202b: KAIT optical upper limit
  18. GRB 241204A: DDOTI Upper Limits on the Afterglow
  19. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  20. EP241202b: Kinder optical counterpart candidate
  21. EP241202b: EP detection of a fast X-ray transient
  22. EP241201a: NOT optical observations
  23. GRB 241128A: Swift/UVOT Upper Limits
  24. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  25. EP241201a: Kinder optical counterpart candidate
  26. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  27. EP241126a: 1.6m Mephisto Optical Upper Limits
  28. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  30. GRB 241128A: AbAO optical upper limit
  31. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  32. GRB 241127A: PRIME near-infrared detection
  33. GRB 241128A: Mondy optical observations
  34. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  35. Swift-XRT observations of IceCube -241127A
  36. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  37. GRB 241128A: Enhanced Swift-XRT position
  38. GRB 241128A: NOT optical observations
  39. GRB 241128A: LCO optical detection
  40. GRB 241128A: Swift-XRT afterglow detection
  41. GRB 241128A: Swift detection of a burst
  42. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  43. GRB 241127A: Swift/UVOT Detection
  44. GRB 241127A: Enhanced Swift-XRT position
  45. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  46. EP241126a: WFST Observations
  47. GRB 241127A: Swift detection of a burst with an optical counterpart
  48. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  49. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  50. EP241126a: Optical Upper limits with Kinder observations
  51. IPN triangulation of GRB 241114B
  52. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  53. EP241126a: TRT optical counterpart detection
  54. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  55. EP241126a: EP detection of a fast X-ray transient
  56. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  57. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  58. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  59. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  60. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  61. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  62. GRB 241026A: radio detection with the VLA
  63. EP241125a: Optical upper limit with Kinder observations
  64. EP241125a: EP detection of an X-ray transient
  65. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  66. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  67. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  68. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  69. GRB 241120A: GRBAlpha detection
  70. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  71. IPN triangulation of GRB 241117A
  72. GRB 241026A: VIRT Optical Upper Limit
  73. GRB 241025A: VIRT Optical Upper Limit
  74. GRB241120A: OHP/T193 optical observations
  75. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  76. GRB 241120A: Mondy and AbAO optical observations
  77. EP241119a: Optical upper limits with Kinder observations
  78. EP241119a: GIT optical upper limits
  79. EP241119a : J-band observations with WINTER
  80. EP241119a: EP detection of a fast X-ray transient
  81. GRB 241112B: Mephisto further optical observations
  82. GRB 241030A: J-band observations
  83. GRB 241115a: PRIME near-infrared upper limits
  84. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  85. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  86. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  87. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  88. GRB 241115A: Swift-XRT afterglow detection
  89. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  90. GRB 241115A: Mephisto upper limits
  91. GRB 241113B: Mephisto upper limits
  92. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  93. GRB 241115D / EP 241115a: SVOM/GRM observation
  94. The EP-WXT trigger 01709120856 is likely a flaring star
  95. EP241113a: Swift XRT weak detection
  96. GRB 241115A: LCOGT Optical Upper Limits
  97. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  98. EP241115a: EP detection of a fast X-ray transient
  99. GRB 241115A: Swift detection of a burst
  100. EP 241113a: LBT possible optical counterpart

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