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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"

28306 results found.

  1. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  2. EP241109a: confirmation of a stellar flare by BOOTES-7
  3. GRB 241108A: Swift-XRT observations
  4. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  5. EP241107a: KAIT optical observations
  6. GRB 241030A: TESS observations
  7. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  8. EP241107a: Kinder optical follow-up observations
  9. GRB 241025A: radio detection with the VLA
  10. EP241107a: AKO Optical Afterglow Follow-Up Observations
  11. EP241107a: GSP detects optical counterpart
  12. GRB 241105A: SVOM/GRM observation
  13. EP241107a: OHP/T193 photometric and spectroscopic observations
  14. GRB 241105a: PRIME near-infrared upper limits
  15. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  16. EP241107a: GIT optical observations
  17. EP241107a: SVOM/C-GFT optical observations
  18. EP241107a: AKO Optical Afterglow Detection
  19. GRB 241025A: LBT optical observations
  20. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  21. GRB 241105A: Swift/UVOT Detection
  22. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  23. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  24. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  25. GRB 241105A: Swift-XRT afterglow detection
  26. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  27. GRB 241104A: Swift-XRT observations
  28. GRB 240511A: LCO upper limits
  29. GRB 241104A: Fermi GBM Observation
  30. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  31. GRB 241104A: SVOM/VT optical candidate
  32. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  33. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  34. EP241104a: EP detection of GRB 241104A X-ray emission
  35. GRB 241010A: host galaxy redshift z = 0.977
  36. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  37. GRB 240821A: further radio observations with the VLA
  38. EP241103a: GIT optical upper limit
  39. EP241021a: OHP/T193 further optical observations
  40. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  41. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  42. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  43. EP241103a: Swift XRT detection and improved X-ray position
  44. EP241021a: continued SOAR observations
  45. EP241101a: Optical upper limits with Kinder observations
  46. EP241101a: OHP/T193 optical observations
  47. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  48. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  49. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  50. EP241103a: GSP optical upper limit
  51. EP241103A: LCO optical observations
  52. EP241103a: an X-ray transient detected by Einstein Probe
  53. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  54. S241102cy: Identification of a GW compact binary merger candidate
  55. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  56. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  57. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  58. GRB241030A: OHP/T193 optical observations
  59. GRB 241101A: FRAM-ORM optical limit
  60. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  61. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  62. EP241021a: Upper limit from Konus-Wind observations
  63. GRB 241101A: Swift-BAT refined analysis
  64. GRB 241030A: further SAO RAS optical observations
  65. GRB 241030A: Optical Observations via Virtual Telescope Project
  66. EP241021a: Liverpool Telescope optical follow-up observations
  67. GRB 241030B: Swift-XRT refined Analysis
  68. GRB 241026A: SAO RAS optical observations
  69. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  70. GRB 241101A: Swift detection of a burst
  71. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  72. EP241021a: OHP/T193 optical observations
  73. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  74. GRB 241030B: Montarrenti Observatory optical upper limit
  75. EP241026b: Liverpool Telescope optical follow-up
  76. GRB 241030A: SAO RAS optical observations
  77. GRB 241030A: Fermi GBM Observation
  78. EP241021a: AMI-LA radio detection
  79. GRB 241030B : GIT optical upper limits
  80. GRB 241030B: LCOGT Optical Upper Limits
  81. GRB 241030B: Swift-BAT refined analysis
  82. GRB 241030A: Swift-BAT refined analysis
  83. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  84. GRB 241030B: Swift/UVOT Detection
  85. GRB 241029A: LCO optical detection
  86. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  87. GRB 241030B : MITSuME Akeno optical upper limits
  88. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  89. GRB 241030B: SVOM/VT optical afterglow observations
  90. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  91. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  92. GRB241030B: Fermi GBM Observation
  93. GRB 241030B: BTA observations
  94. GRB 241029A: SVOM/VT optical afterglow observations
  95. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  96. GRB 241030B: Enhanced Swift-XRT position
  97. GRB241030B: GRANDMA/TAROT Upper Limit
  98. GRB 241030A: Swift-XRT refined Analysis
  99. GRB 241030B: SAO RAS optical observations
  100. GRB 241030B: AKO Optical Afterglow Detection

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