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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"

24642 results found.

  1. GRB 241228A: GROWTH-India telescope optical upper limit
  2. GRB 241228B: TRT optical counterpart confirmation
  3. GRB 241228A: Swift-XRT refined Analysis
  4. GRB 241228A: Swift/UVOT Upper Limits
  5. GRB 241228A: Enhanced Swift-XRT position
  6. GRB 241228A: Swift detection of a burst
  7. IceCube-241224A: Upper limits from a search for additional neutrino events in IceCube
  8. LIGO/Virgo/KAGRA S241225c: Two counterpart neutrino candidates from IceCube neutrino searches
  9. GRB 241212A: VZLUSAT-2 detection
  10. EP241223a: Mondy AZT-33IK optical observations
  11. GRB 241029A: LCO optical observation
  12. GRB 241223A: Swift-XRT observations
  13. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  14. GRB 241029A: AbAO AS-32 optical observations
  15. GRB 241223A: Fermi GBM Detection
  16. Fermi trigger No 756678579: Global MASTER-Net observations report
  17. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  18. EP241223a
  19. EP241223a: EP-WXT detection of a fast X-ray transient
  20. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  21. GRB241113A: 7DT Optical upper limits
  22. GRB 241223A: GOTO optical observations summary
  23. GRB 241105A: JWST photometric observations of the host galaxy
  24. EP241217a: e-MERLIN radio observations
  25. GRB 241223A: BALROG localization (Fermi Trigger 756648531 / GRB 241223506)
  26. The EP-WXT trigger 01709129287 is likely a flaring star
  27. EP241217a: Liverpool Telescope optical upper limit
  28. EP241021a: VLA radio detection
  29. GRB 241218A: Mondy AZT-33IK optical upper limit
  30. EP241217a : Leavitt Observatory optical upper limit
  31. GRB 241217A/EP241217b: tentative VLT spectroscopic redshift z=1.879
  32. EP241217a: 1.6m Mephisto multi-band optical observations
  33. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  34. GRB 241218A: Swift/UVOT Upper Limits
  35. EP241217a: optical upper limit with the Liverpool Telescope
  36. GRB 241209B: EP-FXT afterglow detection
  37. GRB 241218A: NOT optical upper limits
  38. GRB 241218A: Swift-BAT refined analysis
  39. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  40. EP 241217a: NIR detection with P200/WIRC
  41. EP 241217a: Possible J-band detection with WINTER
  42. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  43. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  44. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  45. GRB 241217A / EP241217b: NOT optical upper limits
  46. GRB 241218A: REM optical upper limit
  47. GRB 241217A/EP241217b: REM optical/NIR upper limits
  48. EP241217a: REM optical/NIR upper limits
  49. GRB 241217a: Liverpool Telescope optical follow-up
  50. EP241217a: Liverpool Telescope optical follow-up
  51. GRB 241218A: Swift-XRT refined Analysis
  52. EP241217a: NOT optical observations
  53. EP241217a: GROWTH-India Telescope optical observations
  54. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  55. EP241119a: 7DT Optical upper limits
  56. EP241217a: Xinglong optical follow-up observations
  57. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  58. GRB 241218A: LCOGT Optical Upper Limit
  59. GRB 241218A: Enhanced Swift-XRT position
  60. GRB 241217A: GMG Optical Upper Limit
  61. GRB 241218A: Swift detection of a burst
  62. GRB 241217A : SVOM/VT optical afterglow detection
  63. GRB 241217A: Swift-XRT afterglow detection
  64. GRB 241217A: LCO optical upper limit
  65. GRB 241217A: GRANDMA/TAROT optical upperlimits
  66. EP241217a: Swift-XRT Detection
  67. EP241217A: Non-detection from Fermi-GBM Observations
  68. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  69. EP241217a: Kinder optical follow-up observations
  70. EP241217A: LCO optical observations
  71. EP241217a: Gemini-North detection of the likely optical counterpart
  72. EP241217a: EP detection of an X-ray transient
  73. EP241107a: VLA Radio Observation
  74. GRB 241213A: Swift-BAT refined analysis
  75. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  76. GRB 241215A: Mondy AZT-33IK optical observations
  77. GRB 241212A: Swift-XRT observations
  78. GRB 241215A: Nanshan/HMT optical upper limit
  79. GRB 241215A: Montarrenti Observatory optical upper limit
  80. GRB 241215A: GROWTH-India telescope optical upper limit
  81. GRB 241215A: A long GRB detected by INTEGRAL
  82. Integral GRB241215.58: Global MASTER-Net observations report
  83. GRB 241213B: Swift-XRT observations
  84. GRB 241213A: Swift/UVOT Upper Limits
  85. GRB 241213A: Swift-XRT refined Analysis
  86. GRB 241212A: Fermi GBM detection
  87. EP241208a: NOT optical upper limits
  88. GRB 241213A: LCOGT Optical Upper Limits
  89. GRB 241213B: MAXI/GSC detection
  90. EP241213a: EP detection of An X-ray Transient
  91. GRB 241213A: REM optical/NIR upper limits
  92. GRB 241213A: Enhanced Swift-XRT position
  93. GRB241212A: OHP/T193 optical observations
  94. GRB 241213A: SAO RAS optical upper limit
  95. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  96. GRB 241213A: Swift detection of a burst
  97. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  98. GRB 241212A: AstroSat CZTI detection
  99. GRB 241209B: GRANDMA/TRT upper limit
  100. GRB 241207A: TSHAO Zeiss-1000 optical observations

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