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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"

23685 results found.

  1. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  2. Konus-Wind detection of GRB 241021A
  3. GRB 241105A: SVOM/VT optical afterglow observations
  4. GRB 241105A: Swift-XRT afterglow detection
  5. GRB 241104A: Swift-XRT observations
  6. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  7. GRB 241104A: NOT optical non-detection
  8. GRB 241105A: GOTO tentative optical counterpart candidate
  9. GRB 241104A: SVOM/VT optical candidate
  10. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  11. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  12. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  13. GRB 240821A: further radio observations with the VLA
  14. GRB 241030A: GRBAlpha detection
  15. EP241101a: EP-FXT observations update
  16. EP241103a: GOTO optical upper limit
  17. EP241101a: Optical upper limits with Kinder observations
  18. EP241103a: GSP optical upper limit
  19. EP241103A: LCO optical observations
  20. EP241103a: Global MASTER-Net observations report
  21. EP241101a: Global MASTER-Net observations report
  22. GRB 241029A: GRBAlpha detection
  23. EP241101a: BOOTES-7 optical upper limit
  24. S241102cy: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  26. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  27. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  28. EP241101a: EP-WXT detection of a fast X-ray transient
  29. Swift GRB 241101A: Global MASTER-Net observations report
  30. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  31. EP241021a: Upper limit from Konus-Wind observations
  32. GRB 241101A: Swift-BAT refined analysis
  33. GRB 241030A: further SAO RAS optical observations
  34. GRB 241026A: SAO RAS optical observations
  35. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  36. GRB 241101A: Swift detection of a burst
  37. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  38. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  39. GRB 241030B: Montarrenti Observatory optical upper limit
  40. Fermi trigger No 752083996: Global MASTER-Net observations report
  41. GRB 241030A: SAO RAS optical observations
  42. GRB 241030B: Swift-BAT refined analysis
  43. GRB 241030A: Swift-BAT refined analysis
  44. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  45. EP EP241030a: Global MASTER-Net observations report
  46. GRB 241029A: LCO optical detection
  47. Fermi trigger No 752006065: Global MASTER-Net observations report
  48. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  49. Swift GRB241030.77: Global MASTER-Net observations report
  50. GRB 241030B : MITSuME Akeno optical upper limits
  51. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  52. GRB 241030B: SVOM/VT optical afterglow observations
  53. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  54. GRB 241030B: BTA observations
  55. GRB 241029A: SVOM/VT optical afterglow observations
  56. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  57. GRB 241030B: optical observations from the INAF Asiago Observatory
  58. GRB241030B: GRANDMA/TAROT Upper Limit
  59. GRB 241030A: Swift-XRT refined Analysis
  60. GRB 241030B: SAO RAS optical observations
  61. Konus-Wind detection of GRB 241030A
  62. GRB 241030B: Swift detection of a burst
  63. GRB 241030A: Fermi-LAT detection
  64. GRB 240912A: radio detection with the VLA
  65. Fermi GRB 241030A: Global MASTER-Net observations report
  66. Swift GRB 241030A: Global MASTER-Net observations report
  67. GRB 241026A: Swift-BAT refined analysis
  68. GRB 241030A: SVOM/VT optical afterglow observations
  69. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  70. GRB 241030A : MITSuME Akeno optical afterglow detection
  71. GRB 241030A: TRT optical observations
  72. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  73. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  74. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  75. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  76. GRB 241029A: SAO RAS optical observations
  77. GRB 241026A: SAO RAS optical observations
  78. EP241021a: SAO RAS observations of rebrightening
  79. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  80. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  81. GRB 241026A: Swift/UVOT Upper Limits
  82. GRB 241029A: Swift-XRT observations
  83. GRB 241029A: Fermi GBM Observation
  84. GRB 241029A: GOTO optical afterglow detection
  85. GRB 241029A: MASTER early optical counterpart detection
  86. EP 241026b: LBT possible optical counterpart (brightening source)
  87. GRB 241029A: TRT optical afterglow candidate detection
  88. Fermi trigger No 751861204: Global MASTER-Net observations report
  89. GRB 240821A: Keck/LRIS spectroscopic observations
  90. GRB 241026A: the 100th GRB detected by GRBAlpha
  91. GRB 241026A: TNOT optical counterpart detection
  92. Konus-Wind detection of GRB 241025A
  93. GRB 241026A: GECAM detection
  94. GRB 241025A: further SAO RAS optical observations
  95. GRB 241026A: BTA and Zeiss-1000 optical observations
  96. GRB 241026A Fermi GBM Analysis
  97. GRB 241026A: BTA redshift identification of z = 2.79
  98. GRB 241026A: J-band observations with WINTER
  99. GRB 241025A: SAO RAS optical observations
  100. GRB 241026A: Las Cumbres optical detection

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