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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"

28261 results found.

  1. LIGO/Virgo/KAGRA S241225v: Updated Sky localization
  2. LIGO/Virgo/KAGRA S241225c: Updated Sky localization and EM Bright Classification
  3. GRB241229B: UVOT upper limits
  4. GRB 241228B: Fermi GBM Observation
  5. GRB 241228B: Swift-XRT afterglow detection
  6. GRB 241229B: Fermi GBM Observation
  7. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  8. GRB 241228A: Mondy optical afterglow observations
  9. GRB 241229A: GOTO optical upper limits
  10. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  11. GRB 241228A: NOT optical upper limits
  12. GRB 241228B: LCO optical observation
  13. GRB 241228A: Swift-BAT refined analysis
  14. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  15. GRB 241228A: Fermi GBM Observation
  16. GRB241228B: GROWTH-India Telescope optical observations
  17. GRB 241228B: LCOGT photometry of the likely optical counterpart GOTO24jmz
  18. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  19. GRB 241228A: GROWTH-India telescope optical upper limit
  20. GRB 241228B: TRT optical counterpart confirmation
  21. GRB 241228A: Swift-XRT refined Analysis
  22. GRB 241228A: Swift/UVOT Upper Limits
  23. GRB 241228A: Enhanced Swift-XRT position
  24. GRB 241228A: Swift detection of a burst
  25. IceCube-241224A: Upper limits from a search for additional neutrino events in IceCube
  26. LIGO/Virgo/KAGRA S241225c: Two counterpart neutrino candidates from IceCube neutrino searches
  27. GRB 241212A: VZLUSAT-2 detection
  28. EP241223a: Mondy AZT-33IK optical observations
  29. GRB 241029A: LCO optical observation
  30. GRB 241223A: Swift-XRT observations
  31. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  32. GRB 241029A: AbAO AS-32 optical observations
  33. GRB 241223A: Fermi GBM Detection
  34. Fermi trigger No 756678579: Global MASTER-Net observations report
  35. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  36. EP241223a
  37. EP241223a: EP-WXT detection of a fast X-ray transient
  38. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  39. GRB241113A: 7DT Optical upper limits
  40. GRB 241223A: GOTO optical observations summary
  41. GRB 241105A: JWST photometric observations of the host galaxy
  42. EP241217a: e-MERLIN radio observations
  43. GRB 241223A: BALROG localization (Fermi Trigger 756648531 / GRB 241223506)
  44. The EP-WXT trigger 01709129287 is likely a flaring star
  45. EP241217a: Liverpool Telescope optical upper limit
  46. EP241021a: VLA radio detection
  47. GRB 241218A: Mondy AZT-33IK optical upper limit
  48. EP241217a : Leavitt Observatory optical upper limit
  49. GRB 241217A/EP241217b: tentative VLT spectroscopic redshift z=1.879
  50. EP241217a: 1.6m Mephisto multi-band optical observations
  51. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  52. GRB 241218A: Swift/UVOT Upper Limits
  53. EP241217a: optical upper limit with the Liverpool Telescope
  54. GRB 241209B: EP-FXT afterglow detection
  55. GRB 241218A: NOT optical upper limits
  56. GRB 241218A: Swift-BAT refined analysis
  57. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  58. EP 241217a: NIR detection with P200/WIRC
  59. EP 241217a: Possible J-band detection with WINTER
  60. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  61. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  62. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  63. GRB 241217A / EP241217b: NOT optical upper limits
  64. GRB 241218A: REM optical upper limit
  65. GRB 241217A/EP241217b: REM optical/NIR upper limits
  66. EP241217a: REM optical/NIR upper limits
  67. GRB 241217a: Liverpool Telescope optical follow-up
  68. EP241217a: Liverpool Telescope optical follow-up
  69. GRB 241218A: Swift-XRT refined Analysis
  70. EP241217a: NOT optical observations
  71. EP241217a: GROWTH-India Telescope optical observations
  72. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  73. EP241119a: 7DT Optical upper limits
  74. EP241217a: Xinglong optical follow-up observations
  75. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  76. GRB 241218A: LCOGT Optical Upper Limit
  77. GRB 241218A: Enhanced Swift-XRT position
  78. GRB 241217A: GMG Optical Upper Limit
  79. GRB 241218A: Swift detection of a burst
  80. GRB 241217A : SVOM/VT optical afterglow detection
  81. GRB 241217A: Swift-XRT afterglow detection
  82. GRB 241217A: LCO optical upper limit
  83. GRB 241217A: GRANDMA/TAROT optical upperlimits
  84. EP241217a: Swift-XRT Detection
  85. EP241217A: Non-detection from Fermi-GBM Observations
  86. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  87. EP241217a: Kinder optical follow-up observations
  88. EP241217A: LCO optical observations
  89. EP241217a: Gemini-North detection of the likely optical counterpart
  90. EP241217a: EP detection of an X-ray transient
  91. EP241107a: VLA Radio Observation
  92. GRB 241213A: Swift-BAT refined analysis
  93. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  94. GRB 241215A: Mondy AZT-33IK optical observations
  95. GRB 241212A: Swift-XRT observations
  96. GRB 241215A: Nanshan/HMT optical upper limit
  97. GRB 241215A: Montarrenti Observatory optical upper limit
  98. GRB 241215A: GROWTH-India telescope optical upper limit
  99. GRB 241215A: A long GRB detected by INTEGRAL
  100. Integral GRB241215.58: Global MASTER-Net observations report

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