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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"

21970 results found.

  1. GRB 241128A: Mondy optical observations
  2. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  3. Swift-XRT observations of IceCube -241127A
  4. Swift GRB 241128A: Global MASTER-Net observations report
  5. Fermi-LAT gamma-ray observations of IceCube-241127A
  6. EP241126a: SVOM/VT observations
  7. GRB 241128A: NOT optical observations
  8. GRB 241128A: LCO optical detection
  9. GRB 241128A: 1.5m OSN optical afterglow detection
  10. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  11. Fermi trigger No 754492985: Global MASTER-Net observations report
  12. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  13. GRB 241127A: Swift/UVOT Detection
  14. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  15. EP241126a: WFST Observations
  16. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  17. IceCube Alert 241127.59: Global MASTER-Net observations report
  18. Swift GRB241127.91: Global MASTER-Net observations report
  19. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  20. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  21. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  22. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  23. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  24. EP241126a: Optical Upper limits with Kinder observations
  25. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  26. EP241126a: GSP detects optical counterpart
  27. EP241126a: TRT optical counterpart detection
  28. EP241126a: EP detection of a fast X-ray transient
  29. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  30. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  31. Trigger_18947: Swift ToO observations (retracted)
  32. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  33. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  34. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  35. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  36. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  37. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  38. GRB 241026A: radio detection with the VLA
  39. EP241125a: Optical upper limit with Kinder observations
  40. EP241125a: EP detection of an X-ray transient
  41. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  42. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  43. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  44. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  45. GRB 241113B: SVOM/VT optical afterglow observations
  46. GRB 241105A: ATCA radio detection
  47. GRB241120A: OHP/T193 optical observations
  48. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  49. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  50. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  51. GRB 241120A: Mondy and AbAO optical observations
  52. EP241119a: Optical upper limits with Kinder observations
  53. EP241119a: GIT optical upper limits
  54. GRB 241113A: Possible ATCA Radio detection
  55. EP241119a : J-band observations with WINTER
  56. Integral GRB241120.25: Global MASTER-Net observations report
  57. EP241119a: Global MASTER-Net observations report
  58. EP241119a: EP detection of a fast X-ray transient
  59. GRB 241112B: Mephisto further optical observations
  60. GRB 241030A: J-band observations
  61. GRB 241115a: PRIME near-infrared upper limits
  62. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  63. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  64. Fermi GRB 241118A: Global MASTER-Net observations report
  65. Fermi GRB 241117B: Global MASTER-Net observations report
  66. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  67. Fermi GRB 241117A: Global MASTER-Net observations report
  68. GRB 241115A: Swift-XRT afterglow detection
  69. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  70. EP241113a: Swift XRT weak detection
  71. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  72. Fermi GRB 241115B: Global MASTER-Net observations report
  73. EP241115a: Global MASTER-Net observations report
  74. EP241115a: EP detection of a fast X-ray transient
  75. EP241113a: No Detection in Fermi-GBM Observations
  76. Swift GRB 241115A: Global MASTER-Net observations report
  77. Fermi GRB 241115A: Global MASTER-Net observations report
  78. EP 241113a: LBT possible optical counterpart
  79. GRB 241113B: KAIT Optical Afterglow Candidate
  80. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  81. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  82. GRB 241113A: PRIME near-infrared upper limits
  83. Fermi GRB 241114A: Global MASTER-Net observations report
  84. EP241113a: Global MASTER-Net observations report
  85. GRB 241113B: J-band upper limit from WINTER
  86. GRB 241113A: J-band observations with WINTER
  87. EP241113a : J-band observations with WINTER
  88. GRB 241030A: LCO optical observation
  89. GRB 241113B: Swift-XRT observations
  90. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  91. GRB 241113A: KAIT optical observations
  92. EP241113b: Global MASTER-Net observations report
  93. Fermi-LAT gamma-ray observations of IceCube-241113A
  94. EP241113a: EP on-board trigger and autonomous follow-up observation
  95. EP241107a: SOAR upper limits
  96. GRB 241113A: Swift/UVOT Detection
  97. GRB 241113A: REM detection of the optical/NIR afterglow
  98. GRB 241113B: Swift ToO observations
  99. GRB 241113A: LCO optical observations
  100. GRB241113A: LCOGT (40-cm) optical counterpart detection

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