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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').
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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32506 results found.

  1. GRB030329: RTT150 optical observations and upper limit for a host
  2. GRB 030429: Radio Observations
  3. GRB 030429: redshift from VLT spectroscopy
  4. GRB 030429: IR photometry with IRSF/SIRIUS
  5. GRB030501B triangulation (single error box)
  6. GRB 030329 Optical Observations
  7. GRB030328, optical observation
  8. GRB 030329, BVRI photometry
  9. GRB030429: Optical Observations
  10. GRB030501: TAROT candidate afterglow present in archival images
  11. GRB 030501: TAROT possible candidate counterpart
  12. IPN triangulation of GRB030501 (IBIS event; annulus)
  13. GRB 030429: confirmation of afterglow candidate
  14. GRB030425: CrAO optical observation
  15. GRB 030329 Oprical observations in Rozhen observatory
  16. GRB 030324: Radio Observations
  17. GRB030329 observed as a sudden ionospheric disturbance (SID)
  18. GRB030329, SPM optical observations
  19. GRB 030329, the review of the sky area in plate archive (1950-1998)
  20. GRB 030329: Spectral Evolution of SN 2003dh
  21. GRB 030329: optical spectropolarimetry at VLT
  22. GRB030329: optical polarization
  23. GRB030329, optical observation
  24. GRB030329: 444 AAVSO Measurements
  25. ROTSE-III prompt optical detections of GRB 030418
  26. GRB030418: Upper limits from recent and historical observations.
  27. GRB 030418: Optical afterglow
  28. GRB 030418: Finder for afterglow candidate
  29. GRB 030329 OT position
  30. GRB030329: Optical Observations
  31. OT GRB 030329: early UBVRcIc spectral evolution
  32. GRB030329, UBVRI polarimetry, R-polarization
  33. GRB 030329: SARA Optical Observations
  34. OT GRB 030329: early spectrum
  35. GRB030329: VR Photometry at TNG
  36. GRB030324: Candidate Optical Afterglow
  37. GRB 030413: Optical Observations
  38. GRB 030329 Rc observations
  39. Superluminal motion in GRB 030329 (Correction)
  40. Superluminal motion in GRB 030329
  41. GRB 030329 and SN 2003dh
  42. GRB030329, optical position
  43. GRB 030329 VLBA Observations
  44. GRB 030329: BVRI photometry at Asiago
  45. GRB 030329, light curve flattens
  46. GRB 030329: VLT V-band photometry
  47. If the SN/GRB connection confirmed
  48. GRB 030329: Supernova Confirmed
  49. GRB030329: RTT150 optical observations
  50. GRB030329: Near Infrared Observations at Gunma
  51. GRB030329: HET spectroscopic monitoring
  52. GRB 030329, color evolution
  53. GRB030328, UBVRcIc field photometry
  54. GRB030329: Optical observcations
  55. GRB030329: BV photographic observations
  56. GRB 030329 Optical observations
  57. GRB 030329, color evolution
  58. GRB 030329: possible color change
  59. GRB030329: RTT150 optical observations
  60. GRB 030329: Supernova Spectrum Emerging
  61. GRB030329: RTT150 optical observation
  62. GRB030329: More AAVSO VR obs
  63. GRB030328: R upper limit after 6 hours by MASTER
  64. GRB 030329: BV photographic observations
  65. GRB 030329: SARA Optical Observations
  66. GRB 030329: SARA Optical Observations
  67. GRB030329, fading resumes
  68. GRB 030329, BVRI photometry
  69. GRB030329: Optical observations
  70. SDSS 0.5m PT observations of GRB030329 (correction)
  71. SDSS 0.5m PT observations of GRB030329
  72. GRB 030329, Optical observations
  73. GRB 030329, nearby galaxies
  74. GRB030329, cessation of fading
  75. GRB030329: final R-band light curve by MASTER
  76. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  77. GRB 030329: Sub-millimeter detection
  78. GRB 030329: SARA Optical Observations
  79. GRB 030329: SARA Optical Observations
  80. OT GRB light curves and SN predictions
  81. GRB030329, optical observation
  82. GRB030329, optical observation
  83. GRB030329, new UBVRcIc field photometry
  84. GRB 030329, light curve and SN prediction
  85. GRB030329: optical observations at Tokyo Tech
  86. GRB 030329: optical observations
  87. GRB030329: multiple re-brightening phases
  88. GRB 030329, BRI photometry
  89. GRB030329: Optical observations at Teramo
  90. GRB030329: more 15GHz observations
  91. Further AAVSO V,B,R observations of GRB030329
  92. GRB 030329: Additional Mt. Laguna Optical Observations
  93. GRB 030329: SARA Optical Observations
  94. GRB 030329: Observations with ANDICAM
  95. GRB030329: Optical observations
  96. GRB 030329: Correction to GCN 2056
  97. GRB 030329: fitting parameters and re-brightening
  98. GRB 030329: KAIT optical photometry
  99. GRB030329 Further RBO Optical Observations
  100. triangulation of GRB 030331 (single error box)

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