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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').
Advanced Search

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"

16119 results found.

  1. GRB 250101B: SVOM/GRM observation
  2. GRB 250103A: GOTO optical upper limit
  3. GRB 250103A: SVOM/C-GFT optical upper limit
  4. GRB 250101A: NUTTelA-TAO / BSTI Optical Limits
  5. EP241231b: optical upper limit with the Liverpool Telescope
  6. EP250101a: Xinglong optical upper limit
  7. GRB 250101A: further SAO RAS optical observations
  8. GRB 250101A: LCO optical counterpart detection
  9. GRB 250101A NUTTelA-TAO / BSTI Early Measurements
  10. GRB 250101A: GMG spectroscopic redshift at z ~ 2.481
  11. GRB 250101A: Swift/UVOT Detection
  12. GRB 250101A: 1.6m Mephisto multi-band optical followup
  13. GRB 250101A: Montarrenti Observatory optical observations and rebrightening
  14. GRB 250101A: LCOGT optical afterglow detection
  15. GRB 250101A: OASDG optical observations
  16. GRB 250101A: SAO RAS observations of optical brightening
  17. GRB 250101A: BOOTES-4/MET optical afterglow detection
  18. GRB 250101A: AKO Optical Afterglow Detection
  19. GRB 250101A: SAO RAS optical observations
  20. GRB 250101A: Xinglong-2.16m spectroscopic redshift
  21. GRB 250101A: SVOM/C-GFT early optical observations
  22. GRB 250101A: MASTER earlier OT observations with SOSS emission features
  23. GRB 250101A: Nanshan/HMT optical observations
  24. GRB 250101A : GIT optical detection
  25. GRB 250101A: GMG Optical Observation
  26. GRB 250101A: Swift detection of a burst with an optical counterpart
  27. GRB 241229B: Continued CrAO ZTSh observations
  28. GRB 241228B: Multiband optical monitoring with 1.6m Mephisto
  29. GRB 241229B: SVOM/GRM observation
  30. EP241217A: J band upper limit by SYSU 80cm telescope
  31. GRB 241229B: SAO RAS optical upper limit
  32. GRB 241228B: SAO RAS optical observations
  33. GRB 241229B: CrAO ZTSh possible optical counterpart of SVOM/VT confirmation
  34. GRB 241229A: SAO RAS optical observations
  35. GRB 241229B: SVOM/VT optical candidate
  36. EP240702a: 7DT Optical upper limits
  37. GRB 240606B: 7DT Optical upper limits
  38. GRB241229B: UVOT upper limits
  39. GRB 241228B: D50 optical detection
  40. GRB 241228B: Swift-XRT afterglow detection
  41. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  42. GRB 241228A: Mondy optical afterglow observations
  43. IceCube-241224A: No transient candidates from the Zwicky Transient Facility
  44. GRB 241229A: GOTO optical upper limits
  45. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  46. GRB 241228A: NOT optical upper limits
  47. GRB 241228B: LCO optical observation
  48. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  49. GRB241228B: GROWTH-India Telescope optical observations
  50. GRB 241228B: LCOGT photometry of the likely optical counterpart GOTO24jmz
  51. GRB 241228B: GOTO24jmz optical follow-up observations
  52. GRB 241228A: GROWTH-India telescope optical upper limit
  53. GRB 241228B: TRT optical counterpart confirmation
  54. GRB 241228A: Swift/UVOT Upper Limits
  55. GRB 241228B: GOTO possible optical counterpart candidate
  56. GRB 241217A/EP241217b: continued SOAR observations
  57. EP241223a: Mondy AZT-33IK optical observations
  58. GRB 241029A: LCO optical observation
  59. GRB 241223A: Swift-XRT observations
  60. GRB 241029A: AbAO AS-32 optical observations
  61. EP241223a
  62. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  63. GRB241113A: 7DT Optical upper limits
  64. GRB 241223A: GOTO optical observations summary
  65. GRB 241217A / EP241217b: Non-detection in ATCA Radio Follow-up Observations
  66. GRB 241209B: host galaxy detection and GTC/OSIRIS+ spectroscopy
  67. GRB 241217A/EP241217b: SOAR afterglow detection
  68. EP241217a: Liverpool Telescope optical upper limit
  69. EP241021a: VLA radio detection
  70. GRB 241218A: Mondy AZT-33IK optical upper limit
  71. EP241217a : Leavitt Observatory optical upper limit
  72. GRB 241217A/EP241217b: tentative VLT spectroscopic redshift z=1.879
  73. EP241217a: 1.6m Mephisto multi-band optical observations
  74. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  75. GRB 241218A: Swift/UVOT Upper Limits
  76. EP241217a: optical upper limit with the Liverpool Telescope
  77. GRB 241209B: EP-FXT afterglow detection
  78. GRB 241218A: NOT optical upper limits
  79. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  80. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  81. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  82. GRB 241217A / EP241217b: NOT optical upper limits
  83. GRB 241218A: REM optical upper limit
  84. GRB 241217A/EP241217b: REM optical/NIR upper limits
  85. EP241217a: REM optical/NIR upper limits
  86. GRB 241218a: Liverpool Telescope optical follow-up
  87. GRB 241217a: Liverpool Telescope optical follow-up
  88. EP241217a: Liverpool Telescope optical follow-up
  89. EP241217a: NOT optical observations
  90. EP241217a: GROWTH-India Telescope optical observations
  91. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  92. EP241119a: 7DT Optical upper limits
  93. EP241217a: Xinglong optical follow-up observations
  94. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  95. GRB 241218A: LCOGT Optical Upper Limit
  96. GRB 241217A: GMG Optical Upper Limit
  97. GRB 241217A : SVOM/VT optical afterglow detection
  98. GRB 241217A: LCO optical upper limit
  99. GRB 241217A: GRANDMA/TAROT optical upperlimits
  100. EP241217a: Swift-XRT Detection

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