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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"

8519 results found.

  1. IceCube-200117A: Candidate Counterpart from the Zwicky Transient Facility
  2. IceCube-200117A: Upper limits from a search for additional neutrino events in IceCube
  3. IceCube-200117A: No Neutrino Counterpart in ANTARES data
  4. LIGO/Virgo S200115j: Updated Sky Localization and source properties
  5. LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
  6. IceCube-200117A: Upper limits from Fermi-GBM Observations
  7. IceCube-200117A: IceCube observation of a high-energy neutrino candidate event
  8. LIGO/Virgo S200115j: Upper limits from CALET observations.
  9. LIGO/Virgo S200114f: ZTF Forced Photometry of the Swift Source S200114f_X2
  10. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  11. LIGO/Virgo S200114f: Possible X-ray transient
  12. GRB 200115A: Mondy optical afterglow candidate
  13. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  14. LIGO/Virgo S200116ah: Retraction of GW compact binary merger candidate
  15. LIGO/Virgo S200115j High Rank XRT sources are spurious
  16. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  17. LIGO/Virgo S200115j: upper limits from AGILE/GRID observations
  18. LIGO/Virgo S200115j : no neutrino counterpart candidate in ANTARES search
  19. LIGO/Virgo S200114f: Upper limits from CALET observations.
  20. LIGO/Virgo S200115j: Identification of a GW compact binary merger candidate
  21. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  22. LIGO/Virgo S200115j: Upper limits from IceCube neutrino searches
  23. LIGO/Virgo S200114f: Constraints on a CCSN origin from KM3NeT MeV neutrino search.
  24. LIGO/Virgo S200114f: SAGUARO previous detection of ZTF candidate ZTF20aafeaqk (AT2020vx)
  25. LIGO/Virgo S200114f: upper limits from AGILE-GRID observations
  26. IceCube-200109A: Candidate Counterparts from the Zwicky Transient Facility
  27. LIGO/Virgo S200114f : no neutrino counterpart candidate in ANTARES search
  28. LIGO/Virgo S200114f: Upper limits from Fermi-GBM Observations
  29. LIGO/Virgo S200114f: Identification of a GW unmodeled transient candidate
  30. LIGO/Virgo S200114f: No counterpart candidates in HAWC observations
  31. LIGO/Virgo S200114f: Upper limits from IceCube neutrino searches
  32. LIGO/Virgo S200112r: upper limits from AGILE/GRID observations
  33. LIGO/Virgo S200112r: No counterpart candidates in HAWC observations
  34. LIGO/Virgo S200112r : no neutrino counterpart candidate in ANTARES search
  35. LIGO/Virgo S200112r: Upper limits from IceCube neutrino searches
  36. LIGO/Virgo S200112r: Identification of a GW compact binary merger candidate
  37. IceCube 200109A: No significant detection in HAWC
  38. IceCube-200109A: Upper limits from a search for additional neutrino events in IceCube
  39. IceCube-200107A: Upper limits from a search for additional neutrino events in IceCube
  40. IceCube-200109A: Swift-XRT and UVoT Follow-up Observations
  41. IceCube-200109A: Upper limits from Fermi-GBM Observations
  42. IceCube-200109A: IceCube observation of a high-energy neutrino candidate event
  43. LIGO/Virgo S200105ae: Updated Sky Localization and EM-Bright Probabilities
  44. LIGO/Virgo S200105ae: Gaia Photometric Alerts transient candidate
  45. GRB 200109A: Swift detection of a burst
  46. Fermi-LAT ANTARES coincidence: Upper limits from Fermi-GBM Observations
  47. LIGO/Virgo S200105ae: GW data still under study
  48. Fermi-LAT Gamma-ray Observations of IceCube-200107A
  49. IceCube-200107A: No significant detection in HAWC
  50. LIGO/Virgo S200108v: Retraction of GW compact binary merger candidate
  51. GRB 200107B: Swift detection of a burst
  52. LIGO/Virgo S200105ae: Further study ongoing for GW compact binary merger candidate
  53. IceCube-200107A: Upper limits from Fermi-GBM Observations
  54. IceCube-200107A: IceCube observation of a high-energy neutrino candidate event
  55. LIGO/Virgo S200105ae: AstroSat CZTI upper limits
  56. LIGO/Virgo S200105ae: No counterpart candidates in HAWC observations
  57. LIGO/Virgo S200105ae: Upper limits from IceCube neutrino searches
  58. LIGO/Virgo S200105ae: Upper limits from Fermi-GBM Observations
  59. LIGO/Virgo S200105ae : no neutrino counterpart candidate in ANTARES search
  60. LIGO/Virgo S200105ae: We have issued GCN Notices to support automated processing
  61. LIGO/Virgo S200105ae: A subthreshold GW compact binary merger candidate
  62. IceCube-191231A: Upper limits from a search for additional neutrino events in IceCube
  63. IceCube-191231A: No significant detection in HAWC
  64. IceCube-191231A: No Neutrino Counterpart in ANTARES data
  65. IceCube-191231A: Upper limits from Fermi-GBM Observations
  66. IceCube-191231A: IceCube observation of a high-energy neutrino candidate event
  67. LIGO/Virgo S191216ap: Two candidate counterparts from UKIRT/WFCAM z-band observations
  68. GRB 191228A: Swift detection of a burst
  69. LIGO/Virgo S191225aq: Retraction of GW compact binary merger candidate
  70. LIGO/Virgo S191213g: Pan-STARRS monitoring shows PS19hgw (AT2019wxt) to be fading quickly
  71. LIGO/Virgo S191222n: Updated Sky Localization
  72. LIGO/Virgo S191222n: no counterpart candidate in SVOM/GWAC observations
  73. LIGO/Virgo S191216ap: Updated Source Classification
  74. LIGO/Virgo S191216ap: Upper limits from Insight-HXMT/HE observations
  75. LIGO/Virgo S191216ap: No significant candidates found in Pan-STARRS observations
  76. GRB 191221B: Zadko observatory - Gingin optical observations
  77. LIGO/Virgo S191222n : no neutrino counterpart candidate in ANTARES search
  78. LIGO/Virgo S191222n: upper limits from AGILE-GRID observations
  79. LIGO/Virgo S191222n: No counterpart candidates in HAWC observations
  80. LIGO/Virgo S191222n: Identification of a GW compact binary merger candidate
  81. LIGO/Virgo S191222n: Upper limits from IceCube neutrino searches
  82. GRB 191221B: Swift detection of a burst and a very bright optical candidate
  83. LIGO/Virgo S191216ap: No radio candidates so far in the VLA/JAGWAR galaxy targeted search
  84. GRB 191220A: AbAO optical observations
  85. LIGO/Virgo S191215w: Updated Sky Localization
  86. GRB 191220A: Swift detection of a burst
  87. LIGO/Virgo S191220af: Retraction of GW compact binary merger candidate
  88. LIGO/Virgo S191216ap: Subaru/Hyper Suprime-Cam observations of GW+IceCube+HAWC error region
  89. LIGO/Virgo S191216ap: UPDATED list of galaxies coincident with LIGO/Virgo LALInference skymap and HAWC positions
  90. LIGO/Virgo S191216ap: Updated Sky Localization
  91. LIGO/Virgo S191213g: Lulin Follow-up Observations of AT2019wxt
  92. LIGO/Virgo S191213g: Swift UVOT/XRT observations of Pan-STARRS1 candidate: PS19hgw
  93. LIGO/Virgo S191216ap: No candidates found in J-GEM follow-up observations of HAWC error region
  94. LIGO/VIRGO S191213g: ePESSTO+ spectroscopy of AT2019wxt (PS19hgw)
  95. LIGO/Virgo S191213g: HCT spectroscopy of PS19hgw / AT2019wxt
  96. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  97. LIGO/Virgo S191216ap: No candidates found in CHES observations of HAWC error region
  98. LIGO/Virgo S191216ap and IceCube neutrino: no counterpart candidates from AGILE-GRID observations
  99. LIGO/Virgo S191216ap: GRAWITA Loiano observations of HAWC error region
  100. LIGO/Virgo S191216ap: CORRECTED list of galaxies coincident with LIGO/Virgo and HAWC positions

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