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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"

23611 results found.

  1. GRB241229B: UVOT upper limits
  2. GRB 241228B: Swift-XRT afterglow detection
  3. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  4. GRB 241228A: Mondy optical afterglow observations
  5. GRB 241229A: GOTO optical upper limits
  6. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  7. GRB 241228A: NOT optical upper limits
  8. GRB 241228B: LCO optical observation
  9. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  10. GRB 241229B: Swift detection of a burst
  11. GRB 241228A: Fermi GBM Observation
  12. GRB241228B: GROWTH-India Telescope optical observations
  13. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  14. GRB 241228A: GROWTH-India telescope optical upper limit
  15. GRB 241228B: TRT optical counterpart confirmation
  16. GRB 241228A: Swift-XRT refined Analysis
  17. GRB 241228A: Swift/UVOT Upper Limits
  18. GRB 241228B: GOTO possible optical counterpart candidate
  19. GRB 241228A: Enhanced Swift-XRT position
  20. GRB 241228A: Swift detection of a burst
  21. LIGO/Virgo/KAGRA S241225c: Two counterpart neutrino candidates from IceCube neutrino searches
  22. EP241223a: Mondy AZT-33IK optical observations
  23. GRB 241029A: LCO optical observation
  24. GRB 241223A: Swift-XRT observations
  25. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  26. GRB 241029A: AbAO AS-32 optical observations
  27. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  28. EP241223a
  29. EP241223a: EP-WXT detection of a fast X-ray transient
  30. GRB241113A: 7DT Optical upper limits
  31. GRB 241223A: GOTO optical observations summary
  32. GRB 241105A: JWST photometric observations of the host galaxy
  33. EP241217a: e-MERLIN radio observations
  34. GRB 241209B: host galaxy detection and GTC/OSIRIS+ spectroscopy
  35. EP241217a: Liverpool Telescope optical upper limit
  36. EP241021a: VLA radio detection
  37. GRB 241218A: Mondy AZT-33IK optical upper limit
  38. EP241217a : Leavitt Observatory optical upper limit
  39. EP241217a: 1.6m Mephisto multi-band optical observations
  40. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  41. GRB 241218A: Swift/UVOT Upper Limits
  42. EP241217a: optical upper limit with the Liverpool Telescope
  43. GRB 241218A: NOT optical upper limits
  44. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  45. EP 241217a: NIR detection with P200/WIRC
  46. EP 241217a: Possible J-band detection with WINTER
  47. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  48. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  49. GRB 241217A / EP241217b: NOT optical upper limits
  50. GRB 241218A: REM optical upper limit
  51. GRB 241217A/EP241217b: REM optical/NIR upper limits
  52. EP241217a: REM optical/NIR upper limits
  53. GRB 241218a: Liverpool Telescope optical follow-up
  54. GRB 241217a: Liverpool Telescope optical follow-up
  55. EP241217a: Liverpool Telescope optical follow-up
  56. EP241217a: NOT optical observations
  57. EP241217a: GROWTH-India Telescope optical observations
  58. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  59. EP241119a: 7DT Optical upper limits
  60. EP241217a: Xinglong optical follow-up observations
  61. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  62. GRB 241218A: LCOGT Optical Upper Limit
  63. GRB 241218A: Enhanced Swift-XRT position
  64. GRB 241217A: GMG Optical Upper Limit
  65. GRB 241218A: Swift detection of a burst
  66. GRB 241217A : SVOM/VT optical afterglow detection
  67. GRB 241217A: Swift-XRT afterglow detection
  68. GRB 241217A: LCO optical upper limit
  69. GRB 241217A: GRANDMA/TAROT optical upperlimits
  70. EP241217a: Swift-XRT Detection
  71. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  72. EP241217a: Kinder optical follow-up observations
  73. EP241217A: LCO optical observations
  74. EP241217a: Gemini-North detection of the likely optical counterpart
  75. EP241217a: EP detection of an X-ray transient
  76. EP241107a: VLA Radio Observation
  77. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  78. GRB 241215A: Mondy AZT-33IK optical observations
  79. GRB 241212A: Swift-XRT observations
  80. GRB 241215A: Nanshan/HMT optical upper limit
  81. GRB 241215A: Montarrenti Observatory optical upper limit
  82. GRB 241215A: GROWTH-India telescope optical upper limit
  83. GRB 241209B: SVOM/VT optical continuous fading
  84. GRB 241213A: SVOM/VT optical candidate
  85. GRB 241213A: Swift/UVOT Upper Limits
  86. EP241208a: NOT optical upper limits
  87. GRB 241213A: LCOGT Optical Upper Limits
  88. EP241213a: EP detection of An X-ray Transient
  89. GRB 241213A: REM optical/NIR upper limits
  90. GRB 241213A: Enhanced Swift-XRT position
  91. GRB241212A: OHP/T193 optical observations
  92. GRB 241213A: SAO RAS optical upper limit
  93. GRB 241213A: Swift detection of a burst
  94. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  95. GRB 241209B: GRANDMA/TRT upper limit
  96. GRB 241212A: SVOM detection of a bright long burst
  97. Konus-Wind detection of GRB 241209B
  98. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  99. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  100. GRB 241209D: REM optical/NIR upper limits

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