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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"

21940 results found.

  1. GRB 241105a: PRIME near-infrared upper limits
  2. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  3. EP241107a: GIT optical observations
  4. EP241107a: SVOM/C-GFT optical observations
  5. EP241107a: AKO Optical Afterglow Detection
  6. GRB 241025A: LBT optical observations
  7. EP241107a: EP on-board trigger and autonomous follow-up observation
  8. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  9. GRB 241105A: Swift/UVOT Detection
  10. Konus-Wind detection of GRB 241105A (short with extended emission)
  11. GRB 241105A: Swift-XRT afterglow detection
  12. GRB 241104A: Swift-XRT observations
  13. GRB 240511A: LCO upper limits
  14. GRB 241105A: GOTO tentative optical counterpart candidate
  15. GRB 241104A: SVOM/VT optical candidate
  16. GRB 241105A: Fermi GBM Final Real-time Localization
  17. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  18. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  19. EP241104a: EP detection of GRB 241104A X-ray emission
  20. GRB 241010A: host galaxy redshift z = 0.977
  21. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  22. GRB 240821A: further radio observations with the VLA
  23. GRB 241030A: GRBAlpha detection
  24. EP241103a: GIT optical upper limit
  25. EP241021a: OHP/T193 further optical observations
  26. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  27. EP241103a: Swift XRT detection and improved X-ray position
  28. EP241021a: continued SOAR observations
  29. EP241101a: Optical upper limits with Kinder observations
  30. EP241101a: OHP/T193 optical observations
  31. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  32. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  33. EP241103A: LCO optical observations
  34. EP241103a: an X-ray transient detected by Einstein Probe
  35. GRB 241029A: GRBAlpha detection
  36. EP241101a: BOOTES-7 optical upper limit
  37. S241102cy: Identification of a GW compact binary merger candidate
  38. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  39. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  40. GRB241030A: OHP/T193 optical observations
  41. GRB 241101A: FRAM-ORM optical limit
  42. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  43. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  44. EP241021a: Upper limit from Konus-Wind observations
  45. GRB 241030A: further SAO RAS optical observations
  46. GRB 241030A: Optical Observations via Virtual Telescope Project
  47. EP241021a: Liverpool Telescope optical follow-up observations
  48. GRB 241026A: SAO RAS optical observations
  49. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  50. EP241021a: OHP/T193 optical observations
  51. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  52. GRB 241030B: Montarrenti Observatory optical upper limit
  53. EP241026b: Liverpool Telescope optical follow-up
  54. GRB 241030A: SAO RAS optical observations
  55. EP241021a: AMI-LA radio detection
  56. GRB 241030B : GIT optical upper limits
  57. GRB 241030B: LCOGT Optical Upper Limits
  58. GRB 241030A: Swift-BAT refined analysis
  59. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  60. GRB 241030B: Swift/UVOT Detection
  61. GRB 241029A: LCO optical detection
  62. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  63. GRB 241030B : MITSuME Akeno optical upper limits
  64. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  65. GRB 241030B: SVOM/VT optical afterglow observations
  66. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  67. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  68. GRB 241030B: BTA observations
  69. GRB 241029A: SVOM/VT optical afterglow observations
  70. GRB 241030B: Enhanced Swift-XRT position
  71. GRB241030B: GRANDMA/TAROT Upper Limit
  72. GRB 241030B: SAO RAS optical observations
  73. GRB 241030B: AKO Optical Afterglow Detection
  74. GRB 241030B: Nanshan/HMT optical afterglow detection
  75. Konus-Wind detection of GRB 241030A
  76. GRB 241030B: Swift detection of a burst
  77. GRB 240912A: radio detection with the VLA
  78. GRB 241030A: AKO Optical Afterglow Detection
  79. GRB 241030A: Swift/UVOT Detection
  80. GRB 241030A: SVOM/C-GFT optical observations
  81. GRB 241026A: LBT optical observations
  82. EP241021a: Optical rebrightening observations with Mephisto
  83. GRB 241030A: Multiband optical detection with Mephisto
  84. GRB 241030A: SVOM/VT optical afterglow observations
  85. GRB 241030A : MITSuME Akeno optical afterglow detection
  86. GRB 241030A: Enhanced Swift-XRT position
  87. GRB 241029A: GROWTH-India Telescope optical follow up
  88. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  89. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  90. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  91. GRB 241029A: SAO RAS optical observations
  92. GRB 241026A: SAO RAS optical observations
  93. EP241021a: SAO RAS observations of rebrightening
  94. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  95. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  96. GRB 241026A: Swift/UVOT Upper Limits
  97. GRB 241029A: AKO Optical Afterglow Detection
  98. EP241021a: continued SOAR observations confirm optical rebrightening
  99. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  100. GRB 241029A: Mephisto observations

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