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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"

16277 results found.

  1. GRB 200131A: LCO Optical Detection
  2. GRB 200131A: KAIT Optical Upper Limit
  3. GRB 200131A: RATIR Optical Observations
  4. GRB 200131A: MASTER optical transient detection
  5. GRB 200131A: Swift detection of a burst with an optical counterpart
  6. Fermi-LAT ANTARES 200127.79 coincidence: MASTER alert observation and presence of young pulsar close to error-box
  7. GRB 200127A: Swift/UVOT Upper Limits
  8. GRB 200127A: Mondy optical upper limit
  9. GRB200127A: Nordic Optical telecope optical upper limit
  10. GRB 200125B: DDOTI/OAN optical observations report
  11. GRB 200127A: Nanshan-0.6m optical upper limit
  12. GRB 200127A: AbAO optical upper limit
  13. GRB 200125A: Swift/UVOT Upper Limits
  14. GRB 200125A: Further RATIR Optical Observations and Confirmation of Fading
  15. GRB 200125A: AbAO optical upper limit
  16. GRB 200125A: TNG detection of a NIR counterpart candidate
  17. GRB 200125A: Nanshan-0.6m optical upper limit
  18. GRB 200125A: RATIR Optical Observations
  19. GRB 200122A: Optical upper limit: correction to the GCN circ. 26870
  20. GRB 200115A: Assy optical observations
  21. GRB 200122A: Optical upper limit
  22. GRB 200122A: Mondy optical upper limit
  23. GRB 200122A: MITSuME Akeno optical upper limits
  24. LIGO/Virgo S200115j: Zwicky Transient Facility search for optical counterparts to Swift X-ray sources
  25. GRB 200122A: RATIR Optical Observations
  26. GRB 200122A: Xinglong-2.16m optical upper limit
  27. GRB 200122A: Swift/UVOT Upper Limits
  28. LIGO/Virgo S200115j: Further Swift-XRT sources
  29. GRB 200122A: FRAM-ORM optical limit
  30. GRB 200122A: GOTO non-detection of optical afterglow
  31. LIGO/Virgo S200114f: SOAR spectroscopy of AT2020zf, AT2020ace and AT2020ach
  32. LIGO/Virgo S200115j: No counterpart detection within possible host galaxies observed by the GRAWITA-Savelli telescope
  33. GRB 200115A: Mondy optical observations and correction to GCN 26790
  34. LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
  35. GRB 200115A: AROMA-N Optical Observation
  36. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  37. GRB 200115A: DDOTI/OAN optical observations report
  38. GRB 200115A: Mondy optical afterglow candidate
  39. GRB 200115A: Swift-BAT refined analysis
  40. GRB 200115A: MITSuME Okayama optical upper limits
  41. GRB 200115A: Nanshan-0.6m optical upper limit
  42. LIGO/Virgo S200114f: AT2020vr, AT2020vt, AT2020wa and AT2020wc 10.4m GTC spectroscopy
  43. GRB 200114A: DDOTI/OAN optical observations report
  44. LIGO/Virgo S200114f: No Counterparts in DDOTI/OAN Optical Observations
  45. LIGO/Virgo S200114f: Constraints on a CCSN origin from KM3NeT MeV neutrino search.
  46. LIGO/Virgo S200105ae: AT2020pq, AT2020ps and AT2020pv 10.4m GTC spectroscopy
  47. LIGO/Virgo S200105ae: AT2020pp and AT2020py 10.4m GTC spectroscopy
  48. LIGO/Virgo S200105ae: AT2020oo 10.4m GTC spectroscopy
  49. GRB 200107B: Swift/UVOT Observations
  50. GRB 200109A: Swift/UVOT Upper Limits
  51. Fermi-LAT ANTARES coincidence /ANTARES alert 200108.39: MASTER alert and inspect observation
  52. LIGO/Virgo S200105ae: Candidates from the Zwicky Transient Facility
  53. Swift GRB200107.81: Global MASTER-Net OT detection
  54. GRB 191228A: FRAM-ORM optical limit
  55. GRB 191228A: Early Optical Upper Limits from LCO
  56. GRB 191228A: Mondy optical upper limit
  57. GRB 191228A: Swift/UVOT Upper Limits
  58. GRB 191228A: ePESSTO+ NTT optical upper limit
  59. GRB 191227A: MITSuME Akeno optical upper limits
  60. Swift GRB191227A: Global MASTER-Net OT detection
  61. LIGO/Virgo S191213g: AT2019wxt 10.4m GTC further spectroscopy
  62. Swift trigger 946234/GRB 191226.02 : MASTER obervation
  63. GRB 191221B: ATCA detection of the radio afterglow
  64. LIGO/Virgo S191213g: Pan-STARRS monitoring shows PS19hgw (AT2019wxt) to be fading quickly
  65. GRB 191221B: iTelescope T17 detection
  66. GRB 191221B: iTelescope optical observations
  67. GRB 191221B: ALMA detection
  68. LIGO/Virgo S191216ap: No significant candidates found in Pan-STARRS observations
  69. GRB 191221B: Zadko observatory - Gingin optical observations
  70. GRB 191221B: LCO Optical Detection
  71. GRB 191221B: MASTER VWFC OT yearly detection
  72. GRB 191221B: VLT/X-shooter redshift
  73. GRB 191221B: VIRT Optical Upper Limits
  74. GRB 191221B: MASTER OT detection
  75. GRB 191221B: Swift detection of a burst and a very bright optical candidate
  76. LIGO/Virgo S191216ap: MASTER optical observation
  77. LIGO/Virgo S191213g: VLA follow-up of AT2019wxt/PS19hg
  78. GRB 191220A: Swift/UVOT Upper Limits
  79. GRB 191220A: AbAO optical observations
  80. LIGO/Virgo S191213g: AT2019wxt 10.4m GTC spectroscopy
  81. LIGO/Virgo S191213g : SAO 1-m optical observation of AT2019wxt (PS19hgw)
  82. LIGO/Virgo S191213g: LBT spectrum of AT2019wxt (PS19hgw) reveals a type IIb supernova
  83. LIGO/Virgo S191213g: VLT spectrum of AT2019wxt (PS19hgw) - a probable Ib supernova
  84. LIGO/Virgo S191205ah: AT2019wmy 10.4m GTC spectroscopy
  85. LIGO/Virgo S191213g: MASTER observation of AT2019wxt (PS19hgw)
  86. LIGO/Virgo S191216ap: No candidates found in J-GEM follow-up observations of HAWC error region
  87. LIGO/VIRGO S191213g: LT spectroscopy of AT2019wxt (PS19hgw)
  88. LIGO/Virgo S191213g: AT2019wnh, AT2019wnk and AT2019wrt 10.4m GTC spectroscopy
  89. LIGO/Virgo S191213g: NOT optical spectroscopy of AT2019wxt (PS19hgw)
  90. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  91. LIGO/Virgo S191213g: Pan-STARRS1 discovery of a potential optical counterpart
  92. LIGO/Virgo S191216ap: Nanshan follow-up observations
  93. LIGO/Virgo S191216ap: IceCube event: MASTER OF detection in GW and Neutrino error field
  94. LIGO/Virgo S191213g: MASTER OT J064855.37-055545.7 is a dwarf nova
  95. UKIRT photometry of ZTF19acyldun/AT 2019wrt
  96. LIGO/Virgo S191213g: LCOGT photometry of ZTF19acymaru/AT2019wnh
  97. LIGO/Virgo S191213g: WHT spectroscopy of candidate counterparts
  98. LIGO/Virgo S191213g: GRAWITA TNG classification of ZTF19acykzsk
  99. LIGO/Virgo S191213g: Liverpool Telescope spectroscopy of ZTF candidates
  100. LIGO/Virgo S191205ah: AT2019wix and AT2019wib 10.4m GTC spectroscopy

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