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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

16161 results found.

  1. GRB 241209A: COLIBRÍ Optical Upper Limit
  2. GRB 241209A: Fermi GBM Observation
  3. GRB 241209A: GRANDMA/TAROT upper limit
  4. GRB 241209B: BOOTES-5 optical upper limit
  5. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  6. GRB 241209A: REM optical/NIR observations
  7. GRB 241209D: Swift detection of a burst
  8. GRB 241209A: VLT optical observations
  9. GRB 241209A: GOTO optical upper limits
  10. EP241206a: 1.5m OSN optical limit
  11. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  12. EP241206a: BOOTES Global Network optical limits
  13. GRB 241207C: MASTER optical observations
  14. GRB 241206B: GWAC-F50A optical upper limit
  15. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  16. EP241201a: 1.6m Mephisto Optical Upper Limits
  17. GRB 241204A: COLIBRÍ Optical Upper Limit
  18. EP241202b: KAIT optical upper limit
  19. EP241202b: Kinder optical counterpart candidate
  20. EP241201a: BOOTES-5 optical upper limit
  21. EP241201a: NOT optical observations
  22. GRB 241128A: Swift/UVOT Upper Limits
  23. EP241201a: Kinder optical counterpart candidate
  24. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  25. EP241126a: SOAR observations of the optical counterpart
  26. EP241126a: 1.6m Mephisto Optical Upper Limits
  27. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  28. GRB 241128A: AbAO optical upper limit
  29. EP241126a: NOT optical observations
  30. GRB 241127A: PRIME near-infrared detection
  31. GRB 241128A: Mondy optical observations
  32. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  33. Swift-XRT observations of IceCube -241127A
  34. EP241126a: SVOM/VT observations
  35. GRB 241128A: NOT optical observations
  36. GRB 241128A: LCO optical detection
  37. GRB 241128A: 1.5m OSN optical afterglow detection
  38. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  39. GRB 241127A: Swift/UVOT Detection
  40. GRB 241127A: SVOM/GRM observation
  41. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  42. Swift GRB241127.91: Global MASTER-Net OT detection
  43. EP241126a: WFST Observations
  44. GRB 241127A: Swift detection of a burst with an optical counterpart
  45. Swift GRB241127.91: Global MASTER-Net OT detection
  46. EP241126a: Optical Upper limits with Kinder observations
  47. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  48. EP241126a: EP-FXT follow-up observation update
  49. EP241126a: GSP detects optical counterpart
  50. EP241126a: TRT optical counterpart detection
  51. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  52. GRB 241113B: EP-FXT afterglow detection
  53. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  54. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  55. SVOM/GRM detection of a short burst from SGR 1830
  56. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  57. GRB 241026A: radio detection with the VLA
  58. EP241125a: Optical upper limit with Kinder observations
  59. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  60. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  61. GRB 241113B: SVOM/VT optical afterglow observations
  62. GRB 241105A: ATCA radio detection
  63. GRB 241026A: VIRT Optical Upper Limit
  64. GRB 241025A: VIRT Optical Upper Limit
  65. GRB241120A: OHP/T193 optical observations
  66. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  67. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  68. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  69. GRB 241120A: Mondy and AbAO optical observations
  70. EP241119a: Optical upper limits with Kinder observations
  71. EP241119a: GIT optical upper limits
  72. GRB 241113A: Possible ATCA Radio detection
  73. GRB 241112B: Mephisto further optical observations
  74. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  75. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  76. GRB 241115A: Mephisto upper limits
  77. GRB 241113B: Mephisto upper limits
  78. GRB 241115D / EP 241115a: SVOM/GRM observation
  79. GRB 241115A: LCOGT Optical Upper Limits
  80. EP 241113a: LBT possible optical counterpart
  81. GRB 241113B: KAIT Optical Afterglow Candidate
  82. GRB 241113A: J-band observations with WINTER
  83. GRB 241030A: LCO optical observation
  84. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  85. GRB 241113A: KAIT optical observations
  86. GRB 241113B: SVOM/GRM observation
  87. EP241107a: SOAR upper limits
  88. GRB 241113A: REM detection of the optical/NIR afterglow
  89. GRB 241113A: LCO optical observations
  90. GRB 241112B: GMG Optical Upper Limit
  91. GRB241113A: LCOGT (40-cm) optical counterpart detection
  92. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  93. GRB 241113A: Swift detection of a burst with an optical counterpart
  94. SVOM/GRM detection of a short burst from SGR 1E1841-045
  95. GRB 241105A: ATCA Radio Upper Limits
  96. GRB 241112B: AbAO optical upper limit
  97. GRB 241107A: GROWTH-India telescope optical upper limit
  98. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  99. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  100. GRB 241112B: SVOM/GRM observation

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