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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"

32572 results found.

  1. GRB 250103A: Swift ToO observations
  2. IceCube-250101A: Upper limits from a search for additional neutrino events in IceCube
  3. GRB 250101a: Liverpool Telescope optical follow-up
  4. GRB 250103B: SVOM detection of a long burst
  5. GRB 250103A: Xinglong 2.16m Optical Candidate
  6. Fermi GRB 250102A: Global MASTER-Net observations report
  7. GRB 250101B: SVOM/GRM observation
  8. GRB 250103A: GOTO optical upper limit
  9. GRB 250103A: SVOM/C-GFT optical upper limit
  10. GRB 250101A: NUTTelA-TAO / BSTI Optical Limits
  11. EP241231b: optical upper limit with the Liverpool Telescope
  12. EP250101a: Xinglong optical upper limit
  13. GRB 250101A: Swift-BAT refined analysis
  14. GRB 250101A: further SAO RAS optical observations
  15. GRB 250101A: LCO optical counterpart detection
  16. GRB 250101A NUTTelA-TAO / BSTI Early Measurements
  17. GRB 250101A: GMG spectroscopic redshift at z ~ 2.481
  18. GRB 250101A: Swift/UVOT Detection
  19. GRB 250101A: 1.6m Mephisto multi-band optical followup
  20. GRB 250101A: Montarrenti Observatory optical observations and rebrightening
  21. GRB 250101A: LCOGT optical afterglow detection
  22. GRB 250101A: OASDG optical observations
  23. Fermi GRB 250101B: Global MASTER-Net observations report
  24. GRB 250101A: SAO RAS observations of optical brightening
  25. GRB 250101A: AKO Optical Afterglow Detection
  26. GRB 250101A: SAO RAS optical observations
  27. LIGO/Virgo/KAGRA S250101k: Updated Sky localization and Source Classification
  28. GRB 250101A: Xinglong-2.16m spectroscopic redshift
  29. GRB 250101A: SVOM/C-GFT early optical observations
  30. LIGO/Virgo/KAGRA S250101k: Upper limits from Fermi-GBM Observations
  31. GRB 250101A: MASTER earlier OT observations with SOSS emission features
  32. GRB 250101A: Nanshan/HMT optical observations
  33. GRB 250101A : GIT optical detection
  34. GRB 250101A: GMG Optical Observation
  35. GRB 241217a/EP241217b: ATCA Radio Detection
  36. EP241217a: VLA Radio Detection

  37. LIGO/Virgo/KAGRA S250101k: Identification of a GW compact binary merger candidate
  38. GRB 241229B: Continued CrAO ZTSh observations
  39. LIGO/Virgo/KAGRA S241231bg: Updated Sky localization and EM Bright Classification
  40. LIGO/Virgo/KAGRA S241230ev: Updated Sky localization
  41. LIGO/Virgo/KAGRA S241230bd: Updated Sky localization
  42. GRB 241229A: EP-FXT X-ray afterglow confirmation
  43. GRB 241228B: Multiband optical monitoring with 1.6m Mephisto
  44. GRB 241229B: SVOM/GRM observation
  45. LIGO/Virgo/KAGRA S241231bg: Identification of a GW compact binary merger candidate
  46. EP241217A: J band upper limit by SYSU 80cm telescope
  47. LIGO/Virgo/KAGRA S241230ev: Identification of a GW compact binary merger candidate
  48. GRB 241229B: SAO RAS optical upper limit
  49. GRB 241228B: SAO RAS optical observations
  50. GRB 241229B: CrAO ZTSh possible optical counterpart of SVOM/VT confirmation
  51. GRB 241229A: SAO RAS optical observations
  52. GRB 241229B: SVOM/VT optical candidate
  53. GRB 241229A: Swift-XRT observations
  54. Konus-Wind detection of GRB 241228A
  55. GRB 241229A: EP-FXT afterglow candidates
  56. EP240702a: 7DT Optical upper limits
  57. GRB 240606B: 7DT Optical upper limits
  58. LIGO/Virgo/KAGRA S241230bd: Identification of a GW compact binary merger candidate
  59. GRB 241229B: Swift-BAT refined analysis
  60. LIGO/Virgo/KAGRA S241225v: Updated Sky localization
  61. LIGO/Virgo/KAGRA S241225c: Updated Sky localization and EM Bright Classification
  62. GRB241229B: UVOT upper limits
  63. GRB 241228B: D50 optical detection
  64. GRB 241228B: Fermi GBM Observation
  65. GRB 241229B: Fermi GBM Observation
  66. GRB 241229A: Swift ToO observations
  67. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  68. GRB 241228A: Mondy optical afterglow observations
  69. IceCube-241224A: No transient candidates from the Zwicky Transient Facility
  70. Swift GRB 241229B: Global MASTER-Net observations report
  71. GRB 241229A: GOTO optical upper limits
  72. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  73. GRB 241228A: NOT optical upper limits
  74. GRB 241228B: LCO optical observation
  75. GRB 241228A: Swift-BAT refined analysis
  76. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  77. Fermi GRB 241228B: Global MASTER-Net observations report
  78. GRB 241228A: Fermi GBM Observation
  79. GRB241228B: GROWTH-India Telescope optical observations
  80. Swift GRB 241228A: Global MASTER-Net observations report
  81. GRB 241228B: LCOGT photometry of the likely optical counterpart GOTO24jmz
  82. GRB 241228B: GOTO24jmz optical follow-up observations
  83. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  84. GRB 241228A: GROWTH-India telescope optical upper limit
  85. GRB 241228B: Swift ToO observations
  86. GRB 241228B: TRT optical counterpart confirmation
  87. GRB 241228A: Swift/UVOT Upper Limits
  88. GRB 241228B: GOTO possible optical counterpart candidate
  89. IceCube-241224A: Upper limits from a search for additional neutrino events in IceCube
  90. GRB 241223A: GRBAlpha detection
  91. GRB 241212A: VZLUSAT-2 detection
  92. GRB 241217A/EP241217b: continued SOAR observations
  93. Fermi GRB 241226A: Global MASTER-Net observations report
  94. EP241223a: Mondy AZT-33IK optical observations
  95. GRB 241029A: LCO optical observation
  96. GRB 241223A: Swift-XRT observations
  97. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  98. GRB 241029A: AbAO AS-32 optical observations
  99. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  100. EP241223a

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