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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"

28300 results found.

  1. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  2. EP241107a: KAIT optical observations
  3. GRB 241030A: TESS observations
  4. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  5. EP241107a: Kinder optical follow-up observations
  6. GRB 241025A: radio detection with the VLA
  7. EP241107a: AKO Optical Afterglow Follow-Up Observations
  8. EP241107a: GSP detects optical counterpart
  9. GRB 241105A: SVOM/GRM observation
  10. EP241107a: OHP/T193 photometric and spectroscopic observations
  11. GRB 241105a: PRIME near-infrared upper limits
  12. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  13. EP241107a: GIT optical observations
  14. EP241107a: SVOM/C-GFT optical observations
  15. EP241107a: AKO Optical Afterglow Detection
  16. GRB 241025A: LBT optical observations
  17. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  18. GRB 241105A: Swift/UVOT Detection
  19. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  20. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  21. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  22. GRB 241105A: Swift-XRT afterglow detection
  23. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  24. GRB 241104A: Swift-XRT observations
  25. GRB 240511A: LCO upper limits
  26. GRB 241104A: Fermi GBM Observation
  27. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  28. GRB 241104A: SVOM/VT optical candidate
  29. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  30. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  31. EP241104a: EP detection of GRB 241104A X-ray emission
  32. GRB 241010A: host galaxy redshift z = 0.977
  33. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  34. GRB 240821A: further radio observations with the VLA
  35. EP241103a: GIT optical upper limit
  36. EP241021a: OHP/T193 further optical observations
  37. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  38. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  39. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  40. EP241103a: Swift XRT detection and improved X-ray position
  41. EP241021a: continued SOAR observations
  42. EP241101a: Optical upper limits with Kinder observations
  43. EP241101a: OHP/T193 optical observations
  44. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  45. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  46. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  47. EP241103a: GSP optical upper limit
  48. EP241103A: LCO optical observations
  49. EP241103a: an X-ray transient detected by Einstein Probe
  50. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  51. S241102cy: Identification of a GW compact binary merger candidate
  52. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  53. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  54. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  55. GRB241030A: OHP/T193 optical observations
  56. GRB 241101A: FRAM-ORM optical limit
  57. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  58. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  59. EP241021a: Upper limit from Konus-Wind observations
  60. GRB 241101A: Swift-BAT refined analysis
  61. GRB 241030A: further SAO RAS optical observations
  62. GRB 241030A: Optical Observations via Virtual Telescope Project
  63. EP241021a: Liverpool Telescope optical follow-up observations
  64. GRB 241030B: Swift-XRT refined Analysis
  65. GRB 241026A: SAO RAS optical observations
  66. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  67. GRB 241101A: Swift detection of a burst
  68. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  69. EP241021a: OHP/T193 optical observations
  70. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  71. GRB 241030B: Montarrenti Observatory optical upper limit
  72. EP241026b: Liverpool Telescope optical follow-up
  73. GRB 241030A: SAO RAS optical observations
  74. GRB 241030A: Fermi GBM Observation
  75. EP241021a: AMI-LA radio detection
  76. GRB 241030B : GIT optical upper limits
  77. GRB 241030B: LCOGT Optical Upper Limits
  78. GRB 241030B: Swift-BAT refined analysis
  79. GRB 241030A: Swift-BAT refined analysis
  80. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  81. GRB 241030B: Swift/UVOT Detection
  82. GRB 241029A: LCO optical detection
  83. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  84. GRB 241030B : MITSuME Akeno optical upper limits
  85. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  86. GRB 241030B: SVOM/VT optical afterglow observations
  87. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  88. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  89. GRB241030B: Fermi GBM Observation
  90. GRB 241030B: BTA observations
  91. GRB 241029A: SVOM/VT optical afterglow observations
  92. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  93. GRB 241030B: Enhanced Swift-XRT position
  94. GRB241030B: GRANDMA/TAROT Upper Limit
  95. GRB 241030A: Swift-XRT refined Analysis
  96. GRB 241030B: SAO RAS optical observations
  97. GRB 241030B: AKO Optical Afterglow Detection
  98. GRB 241030B: Nanshan/HMT optical afterglow detection
  99. GRB 241030B: Swift detection of a burst
  100. GRB 240912A: radio detection with the VLA

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