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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

3386 results found.

  1. LIGO/Virgo S190426c: PS1 historical detections and ZTF photometry of Gaia19boq AT2019egk
  2. LIGO/Virgo S190425z: 1.3-m optical imaging of UVOT transient field
  3. LIGO/Virgo S190426c: YAHPT Optical Observation
  4. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  5. LIGO/Virgo S190426c: GRAWITA transients from Asiago Schmidt wide field observations
  6. LIGO/Virgo S190425z: DECam Observations of the UVOT Candidate Region
  7. LIGO/Virgo S190426c: Continued LOAO Observation
  8. LIGO/Virgo S190425z: VISTA K-band observations of the Swift/UVOT Transient
  9. Fermi Trigger 578170097 / GRB 190428783 / GRB190428A: BALROG localization
  10. LIGO/Virgo S190426c: Additional Candidates from the Zwicky Transient Facility
  11. LIGO/Virgo S190426c: Continued infrared wide-field search with Palomar Gattini-IR
  12. LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometric follow-up observation of the Swift/UVOT Transient
  13. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  14. LIGO/Virgo S190425z: No source found at UVOT source location at 6 hrs after LVC report
  15. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  16. LIGO/Virgo S190425z: Lulin observations of the Swift/UVOT transient
  17. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  18. LIGO/Virgo S190426c: MMT Follow-Up Observations
  19. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  20. GRB 190427A: COATLI Optical Observations
  21. LIGO/Virgo S190426c: CNEOST Optical Observations
  22. LIGO/Virgo S190425z: CNEOST Optical Observations
  23. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  24. LIGO/Virgo S190425z: Additional Pan-STARRS transients in the skymap
  25. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  26. LIGO/Virgo S190426c: SAO optical observation
  27. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  28. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  29. LIGO/Virgo S190426c: HAWC follow-up
  30. LIGO/Virgo S190425z: YAHPT Optical Observation
  31. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  32. LIGO/Virgo S190425z: KMTNet Observation
  33. LIGO/Virgo S190425z: Swope follow-up observations
  34. LIGO/Virgo S190425z: KPED Follow-Up Observations
  35. LIGO/Virgo S190425z: OVRO-LWA simultaneous low frequency radio observations of localization region
  36. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  37. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  38. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  39. LIGO/Virgo S190425z: Fermi GBM Observations
  40. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  41. Fermi GRB190425.09 Global MASTER-Net observations report
  42. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  43. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  44. Fermi GRB190420.98 Global MASTER-Net observations report
  45. Fermi GRB190419.41 Global MASTER-Net observations report
  46. LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
  47. LIGO/Virgo S190408an: MAXI/GSC Observations
  48. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  49. LIGO/Virgo S190408an: CALET Observations
  50. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  51. GRB 140408A: MAXI/GSC detection
  52. GRB 140404B: MAXI/GSC detection
  53. GRB 190331B: Swift observations of a ground-detected burst
  54. GRB 190326A: 2.2m CAHA telescope optical limit
  55. Swift Trigger 895479: Detection of GRO J2058+42
  56. Swift Trigger 895257: Detection of GRO J2058+42 in outburst
  57. GRB 190326A: Swift detection of a short burst
  58. SWIFT GRB190323.85 Global MASTER-Net observations report
  59. Swift Trigger 894268: Detection of GRO J2058+42 in outburst
  60. Fermi Trigger 574676902 / GRB 190319353: BALROG localization
  61. GRB190219A: MASTER Global Robotic Net optical observation
  62. GRB190211A: GROWTH-India detection of optical afterglow
  63. GRB 190211A: DOAO optical observation
  64. Trigger 888312: Swift detection of 4U 1901+03
  65. GRB 190204A: MAXI/GSC detection
  66. Swift Trigger 887541: Swift detection of Swift J1728.9-3613
  67. IPN Triangulation of GRB 190129B (long/extremely bright)
  68. Swift Trigger 886157: MASTER optical observation
  69. Trigger 885456: Swift detection of MAXI J1631-479
  70. GRB 190114C: RTT150 optical observations
  71. GRB 190114B: optical afterglow observations in Mondy and Abastumani observatories
  72. GRB 190114B: Mondy optical afterglow detection
  73. GRB 190114C: NOT optical counterpart and redshift
  74. Konus-Wind observation of GRB 190103A
  75. GRB 190109A: Swift-BAT refined analysis
  76. Trigger 882561: Swift detection of MAXI J1631-479
  77. GRB 181228A: Mondy and AbAO optical upper limits
  78. GRB 181228A: possible NOT optical detection
  79. GRB 181228A: Xinglong-2.16m optical upper limit
  80. FRB 181228: Global MASTER Net optical inspection
  81. GRB 181227A: Global MASTER Net oprtical inspection
  82. Swift Trigger 880127 is not a GRB
  83. GRB 181228A: TSHAO optical upper limit
  84. GRB 181228A: Fermi GBM observation
  85. GRB 181228A: Global MASTER Net OT detection
  86. GRB 181228A: REM NIR detection
  87. GRB 181126A: MeerKAT radio observation
  88. GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
  89. Swift Trigger 874754 is likely not an astrophysical event
  90. GRB 181201A: Zeiss-1000/CrAO optical observations
  91. GRB 181201A: Swift-XRT afterglow detection
  92. Short-duration GRB 181121.4: MASTER-Tavrida possible OT detection near the PGC galaxy during large Fermi error box inspection
  93. GRB 181028A: CALET Gamma-Ray Burst Monitor detection
  94. GRB 181030A: Swift detection of a burst with a possible optical counterpart
  95. GRB 181028A: Fermi GBM observation
  96. GRB 181028A: Fermi-LAT detection
  97. GRB 181027A: Swift detection of a burst
  98. Swift Trigger 866757: is probably not a GRB
  99. GRB 181011A: MAXI/GSC detection
  100. GRB 181008A: Insight-HXMT/HE detection

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