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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').
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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"

21977 results found.

  1. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  2. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  3. GRB241030A: OHP/T193 optical observations
  4. EP241101a: EP-WXT detection of a fast X-ray transient
  5. Swift GRB 241101A: Global MASTER-Net observations report
  6. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  7. EP241021a: Upper limit from Konus-Wind observations
  8. GRB 241030A: further SAO RAS optical observations
  9. GRB 241030A: Optical Observations via Virtual Telescope Project
  10. EP241021a: Liverpool Telescope optical follow-up observations
  11. GRB 241026A: SAO RAS optical observations
  12. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  13. EP241021a: OHP/T193 optical observations
  14. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  15. GRB 241030B: Montarrenti Observatory optical upper limit
  16. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  17. Fermi trigger No 752083996: Global MASTER-Net observations report
  18. GRB 241030A: SAO RAS optical observations
  19. EP241021a: AMI-LA radio detection
  20. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  21. GRB 241030B: Swift/UVOT Detection
  22. EP EP241030a: Global MASTER-Net observations report
  23. GRB 241029A: LCO optical detection
  24. Fermi trigger No 752006065: Global MASTER-Net observations report
  25. Swift GRB241030.77: Global MASTER-Net observations report
  26. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  27. GRB 241030B: SVOM/VT optical afterglow observations
  28. GRB 241030B: BTA observations
  29. GRB 241029A: SVOM/VT optical afterglow observations
  30. GRB 241030B: optical observations from the INAF Asiago Observatory
  31. GRB241030B: GRANDMA/TAROT Upper Limit
  32. GRB 241030B: SAO RAS optical observations
  33. GRB 241030B: Nanshan/HMT optical afterglow detection
  34. GRB 240912A: radio detection with the VLA
  35. Fermi GRB 241030A: Global MASTER-Net observations report
  36. Swift GRB 241030A: Global MASTER-Net observations report
  37. GRB 241030A: Swift/UVOT Detection
  38. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  39. GRB 241030A: SVOM/C-GFT optical observations
  40. GRB 241026A: LBT optical observations
  41. EP241021a: Optical rebrightening observations with Mephisto
  42. GRB 241030A: Multiband optical detection with Mephisto
  43. GRB 241030A: SVOM/VT optical afterglow observations
  44. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  45. GRB 241030A: TRT optical observations
  46. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  47. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  48. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  49. GRB 241029A: SAO RAS optical observations
  50. GRB 241026A: SAO RAS optical observations
  51. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  52. EP241021a: SAO RAS observations of rebrightening
  53. EP241021a: ATCA radio observations
  54. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  55. GRB 241026A: Swift/UVOT Upper Limits
  56. GRB 241029A: Swift-XRT observations
  57. GRB 241029A: GOTO optical afterglow detection
  58. EP241021a: continued SOAR observations confirm optical rebrightening
  59. GRB 241029A: MASTER early optical counterpart detection
  60. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  61. GRB 241029A: Mephisto observations
  62. EP 241026b: LBT possible optical counterpart (brightening source)
  63. GRB 241029A: TRT optical afterglow candidate detection
  64. GRB 241029A: Swift ToO observations
  65. Fermi trigger No 751861204: Global MASTER-Net observations report
  66. GRB 240821A: Keck/LRIS spectroscopic observations
  67. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  68. GRB 241026A: LBT redshift confirmation
  69. GRB 241025A: further SAO RAS optical observations
  70. GRB 241026A: BTA and Zeiss-1000 optical observations
  71. EP241026B: GROWTH-India Telescope optical upper limit
  72. GRB 241025A: Swift/UVOT Detection
  73. GRB 241026A: GROWTH-India Telescope optical observations
  74. GRB 241026A: J-band observations with WINTER
  75. GRB 241025A: SAO RAS optical observations
  76. GRB 241025A: Mondy optical observations
  77. EP241021a: SOAR observations of the optical counterpart
  78. EP241021a: further SAO RAS optical observations
  79. EP 241026b: LBT optical observations
  80. EP241021a: e-MERLIN radio observation
  81. EP EP241026b: Global MASTER-Net observations report
  82. GRB 241026A: KAIT optical observations
  83. EP241026b: EP detection of a fast X-ray transient
  84. Fermi trigger No 751616906: Global MASTER-Net observations report
  85. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  86. GRB 241026A: SAO RAS observations of possible optical afterglow
  87. Fermi GRB 241026A: Global MASTER-Net observations report
  88. Swift GRB241026.95: Global MASTER-Net observations report
  89. GRB241025A: 1.3m DFOT optical afterglow detection
  90. EP241021a: optical follow-up observations with Xinglong Observatory
  91. ​GRB 241025A: optical photometry from Konkoly
  92. GRB 241025A: GROWTH-India Telescope optical observations
  93. GRB 241025A: COLIBRÍ Detection of the Afterglow
  94. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  95. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  96. Fermi trigger No 751563375: Global MASTER-Net observations report
  97. Fermi trigger No 751554401: Global MASTER-Net observations report
  98. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  99. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  100. EP 241021a: Swift-XRT observations

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