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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"

28286 results found.

  1. GRB 241009A: LCO optical upper limits
  2. Integral GRB241013.04: Global MASTER-Net observations report
  3. LIGO/Virgo/KAGRA S241009em: Updated Sky localization
  4. LIGO/Virgo/KAGRA S241011k: Updated Sky localization
  5. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  6. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  7. GRB 241009A: GRANDMA optical upper limits
  8. GRB 241009A: Swift-XRT afterglow detection
  9. GRB 241010A: JinShan optical observations and potential host galaxy
  10. GRB 241010A: Swift-XRT refined Analysis
  11. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  12. Fermi trigger No 750211959: Global MASTER-Net observations report
  13. Fermi trigger No 750291012: Global MASTER-Net observations report
  14. GRB 241010A: J-band observations with WINTER
  15. LIGO/Virgo/KAGRA S241009an: Updated Sky localization
  16. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  17. GRB 241010A: Enhanced Swift-XRT position
  18. GRB 241010A: LCO optical observations
  19. GRB 241010A: Swift detection of a burst with an optical counterpart
  20. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  21. GRB 241006A: Swift-BAT refined analysis
  22. LIGO/Virgo/KAGRA S241009l: Updated Sky localization
  23. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  24. GRB 241008A: Fermi GBM Observation
  25. GRB 241002B: Swift-XRT afterglow detection
  26. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  27. GRB 241002A: NOT optical upper limits
  28. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  29. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  30. IceCube-241006A: No candidates from the Zwicky Transient Facility
  31. GRB 241006A: GRANDMA optical upper limits
  32. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  33. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  34. GRB 240910A: LBT optical observations
  35. GRB 241006A: Swift-XRT refined Analysis
  36. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  37. GRB 241006A: PRIME near-infrared upper limits
  38. GRB 241006A: Swift/UVOT Upper Limits
  39. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  40. GRB 241001A: Swift-XRT afterglow detection
  41. GRB 241006A: Enhanced Swift-XRT position
  42. GRB 241006A: Swift detection of a burst
  43. GRB 240930B: SVOM/C-GFT optical upper limit
  44. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  45. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  46. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  47. GRB 241002B: Fermi GBM Observation
  48. GRB 241002B: Swift-XRT observations
  49. GRB 241002C: SVOM/C-GFT optical upper limit
  50. GRB 241002A: Swift-BAT refined analysis
  51. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  52. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  53. GRB 241002B: PRIME near-infrared detection
  54. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  55. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  56. IPN triangulation of GRB 240930B / EP 240930a
  57. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  58. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  59. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  60. GRB 241002C : MITSuME Akeno optical upper limits
  61. LIGO/Virgo/KAGRA S240925n: Updated Sky localization
  62. NuEm-240926A: Upper limits from a search for coincident neutrino events in IceCube
  63. GRB241001A: REM optical/NIR upper limits
  64. LIGO/Virgo/KAGRA S241002e: Updated Sky localization
  65. GRB 241002A: Swift/UVOT Upper Limits
  66. EP240930a: Liverpool Telescope observations
  67. GRB 241002A: Swift-XRT refined Analysis
  68. GRB 241002A: LCOGT Optical Upper Limits
  69. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  70. GRB 241001A: Swift/UVOT Detection
  71. GRB 240929A: Liverpool Telescope prompt followup observations
  72. GRB 241001A: Swift-XRT observations
  73. GRB241001A: optical afterglow candidate
  74. GRB 241002A: Enhanced Swift-XRT position
  75. GRB 241001A: BOOTES-6/DPRT optical upper limit
  76. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  77. GRB 241002A: Swift detection of a burst
  78. LIGO/Virgo/KAGRA S240930du: Updated Sky localization
  79. GRB 240930B: Fermi GBM Observation
  80. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  81. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  82. EP240930a: EP-WXT detection of a fast X-ray transient
  83. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  84. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  85. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  86. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  87. AMON NuEM 240926A: Swift XRT Follow-up
  88. GRB 240929A : Leavitt Observatory optical upper limit
  89. GRB 240825A: LBT optical observations
  90. GRB 240928A: SVOM/GRM observation
  91. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  92. Fermi trigger No 749339671: Global MASTER-Net observations report
  93. GRB 240929A long GRB detected by INTEGRAL
  94. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  95. Swift Trigger 1256950 is probably not a GRB
  96. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  97. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  98. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  99. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  100. GRB 240926A: SVOM/GRM observation

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