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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"

32739 results found.

  1. EP241021a: GOTO optical upper limits
  2. Konus-Wind detection of GRB 241018A
  3. GRB 241018A: SVOM/GRM observation
  4. GRB 241018A/sb24101802: Mephisto optical upper limit
  5. GRB 241017A/sb24101702: Mephisto optical upper limit
  6. GRB 241018A: Mondy optical upper limit
  7. GRB 241018A: SVOM/VT further analysis and counterpart confirmed
  8. GRB 241018A: GROWTH-India telescope optical upper limit
  9. GRB241018A: XingLong Optical Upper Limit
  10. GRB 241018A: REM optical/NIR upper limits
  11. GRB 241018A: NOT optical observations
  12. GRB 241017A: SVOM/VT follow-up and optical upper limit
  13. GRB 241018A: SVOM/VT follow-up and optical candidate
  14. GRB 241018A: LCO/0.4m optical upper limits
  15. GRB 241018A: Swift ToO observations
  16. GRB 241006A: VIRT Optical Upper Limit
  17. GRB 240727A: VIRT Optical Upper Limit
  18. GRB 241018A: X-ray afterglow candidate observed by MXT
  19. GRB 241016B: Fermi GBM Observations
  20. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources
  21. GRB 241001A: EP-FXT afterglow detection
  22. GRB 241017A: GROWTH-India Telescope optical upper limit
  23. GRB241017A: TOO Observations by SVOM/MXT
  24. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  25. GRB 241017A: J-band upper limit from WINTER
  26. GRB 241016B: SVOM/GRM observation
  27. GRB 241017A: Swift ToO observations
  28. Fermi GRB 241016B: Global MASTER-Net observations report
  29. Fermi GRB 241016A: Global MASTER-Net observations report
  30. GRB 241010A: Swift-BAT refined analysis
  31. GRB 241013B: Fermi GBM Observation
  32. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  33. GRB 241013A: Fermi GBM Observation
  34. GRB 240916A: radio detection with the VLA
  35. GRB241013A: REM observations
  36. GRB 241009A: LCO optical upper limits
  37. GRB 241013B: SVOM/GRM observation
  38. Fermi GRB 241013B: Global MASTER-Net observations report
  39. GRB 241013A: a long GRB detected by INTEGRAL
  40. LIGO/Virgo/KAGRA S241009em: Updated Sky localization
  41. LIGO/Virgo/KAGRA S241011k: Updated Sky localization
  42. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  43. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  44. GRB 241009A: GRANDMA optical upper limits
  45. GRB 241010A: JinShan optical observations and potential host galaxy
  46. GRB 241006A: ATCA Radio Upper Limits
  47. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  48. Swift GRB 241010A: Global MASTER-Net observations report
  49. GRB 241010A: J-band observations with WINTER
  50. LIGO/Virgo/KAGRA S241009an: Updated Sky localization
  51. Fermi GRB 241010B: Global MASTER-Net observations report
  52. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  53. GRB 241010A: LCO optical observations
  54. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  55. GRB 241006A: Swift-BAT refined analysis
  56. GRB 241009A: Swift ToO observations
  57. LIGO/Virgo/KAGRA S241009l: Updated Sky localization
  58. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  59. GRB 241008A: Fermi GBM Observation
  60. GRB 241008A: Fermi-LAT detection
  61. GRB 241002B: Swift-XRT afterglow detection
  62. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  63. GRB 241002A: NOT optical upper limits
  64. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  65. Fermi GRB 241008A: Global MASTER-Net observations report
  66. IceCube-241006A: No candidates from the Zwicky Transient Facility
  67. GRB 241006A: GRANDMA optical upper limits
  68. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  69. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  70. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  71. GRB 240910A: LBT optical observations
  72. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  73. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  74. GRB 241006A: PRIME near-infrared upper limits
  75. GRB 241006A: Swift/UVOT Upper Limits
  76. GRB 241006A: SVOM/VT follow-up and optical upper limit
  77. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  78. GRB 240930B: SVOM/C-GFT optical upper limit
  79. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  80. GRB 240930B / EP 240930a: SVOM/GRM observation
  81. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  82. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  83. GRB 241002B: Fermi GBM Observation
  84. GRB 241002B: Swift-XRT observations
  85. GRB 241002C: SVOM/C-GFT optical upper limit
  86. GRB 241002A: Swift-BAT refined analysis
  87. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  88. GRB 241002B: Swift ToO observations
  89. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  90. Konus-Wind detection of GRB 240926A
  91. GRB 241002B: PRIME near-infrared detection
  92. GRB 241002C: Swift ToO observations
  93. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  94. IPN triangulation of GRB 240930B / EP 240930a
  95. GRB 241001A : SVOM/VT optical detection
  96. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  97. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  98. GRB 240930B: CALET Gamma-Ray Burst Monitor detection
  99. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  100. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations

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