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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"

28292 results found.

  1. EP241107a: GSP detects optical counterpart
  2. GRB 241105A: SVOM/GRM observation
  3. EP241107a: OHP/T193 photometric and spectroscopic observations
  4. GRB 241105a: PRIME near-infrared upper limits
  5. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  6. EP241107a: GIT optical observations
  7. EP241107a: SVOM/C-GFT optical observations
  8. EP241107a: AKO Optical Afterglow Detection
  9. GRB 241025A: LBT optical observations
  10. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  11. GRB 241105A: Swift/UVOT Detection
  12. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  13. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  14. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  15. GRB 241105A: Swift-XRT afterglow detection
  16. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  17. GRB 241104A: Swift-XRT observations
  18. GRB 240511A: LCO upper limits
  19. GRB 241104A: Fermi GBM Observation
  20. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  21. GRB 241104A: SVOM/VT optical candidate
  22. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  23. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  24. EP241104a: EP detection of GRB 241104A X-ray emission
  25. GRB 241010A: host galaxy redshift z = 0.977
  26. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  27. GRB 240821A: further radio observations with the VLA
  28. EP241103a: GIT optical upper limit
  29. EP241021a: OHP/T193 further optical observations
  30. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  31. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  32. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  33. EP241103a: Swift XRT detection and improved X-ray position
  34. EP241021a: continued SOAR observations
  35. EP241101a: Optical upper limits with Kinder observations
  36. EP241101a: OHP/T193 optical observations
  37. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  38. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  39. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  40. EP241103a: GSP optical upper limit
  41. EP241103A: LCO optical observations
  42. EP241103a: an X-ray transient detected by Einstein Probe
  43. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  44. S241102cy: Identification of a GW compact binary merger candidate
  45. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  46. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  47. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  48. GRB241030A: OHP/T193 optical observations
  49. GRB 241101A: FRAM-ORM optical limit
  50. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  51. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  52. EP241021a: Upper limit from Konus-Wind observations
  53. GRB 241101A: Swift-BAT refined analysis
  54. GRB 241030A: further SAO RAS optical observations
  55. GRB 241030A: Optical Observations via Virtual Telescope Project
  56. EP241021a: Liverpool Telescope optical follow-up observations
  57. GRB 241030B: Swift-XRT refined Analysis
  58. GRB 241026A: SAO RAS optical observations
  59. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  60. GRB 241101A: Swift detection of a burst
  61. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  62. EP241021a: OHP/T193 optical observations
  63. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  64. GRB 241030B: Montarrenti Observatory optical upper limit
  65. EP241026b: Liverpool Telescope optical follow-up
  66. GRB 241030A: SAO RAS optical observations
  67. GRB 241030A: Fermi GBM Observation
  68. EP241021a: AMI-LA radio detection
  69. GRB 241030B : GIT optical upper limits
  70. GRB 241030B: LCOGT Optical Upper Limits
  71. GRB 241030B: Swift-BAT refined analysis
  72. GRB 241030A: Swift-BAT refined analysis
  73. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  74. GRB 241030B: Swift/UVOT Detection
  75. GRB 241029A: LCO optical detection
  76. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  77. GRB 241030B : MITSuME Akeno optical upper limits
  78. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  79. GRB 241030B: SVOM/VT optical afterglow observations
  80. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  81. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  82. GRB241030B: Fermi GBM Observation
  83. GRB 241030B: BTA observations
  84. GRB 241029A: SVOM/VT optical afterglow observations
  85. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  86. GRB 241030B: Enhanced Swift-XRT position
  87. GRB241030B: GRANDMA/TAROT Upper Limit
  88. GRB 241030A: Swift-XRT refined Analysis
  89. GRB 241030B: SAO RAS optical observations
  90. GRB 241030B: AKO Optical Afterglow Detection
  91. GRB 241030B: Nanshan/HMT optical afterglow detection
  92. GRB 241030B: Swift detection of a burst
  93. GRB 240912A: radio detection with the VLA
  94. GRB 241030A: AKO Optical Afterglow Detection
  95. GRB 241030A: Swift/UVOT Detection
  96. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  97. GRB 241026A: Swift-BAT refined analysis
  98. GRB 241030A: SVOM/C-GFT optical observations
  99. GRB 241026A: LBT optical observations
  100. EP241021a: Optical rebrightening observations with Mephisto

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