W Comae multiwavelength SED

Names and position

Also known as 1FGL J1221.5+2814, 1FLAT J122131.7+281358, 1OUNYU J122132+2813.9, 2FGL J1221.4+2814, 3FGL J1221.4+2814, 4FGL J1221.5+2814, 5BZB J1221+2813, BZB J1221+2813, CRATES J122131+281357, ON231, QSO B1219+285, SDSS J122131.69+281358.4, TeV J1221+282, TXS 1219+285.

• Class: BL Lac
• Redshift: z = 0.102
• Fermi-LAT (4FGL): 4FGL J1221.5+2814
• Position (ICRS): RA 185.38204°, Dec 28.23292°
• Galactic: l 201.735°, b 83.288°

Other names and measurements: NED and SIMBAD within 5″ of this position.

The SED

• Data: 6,449 points (4 upper limits) from 48 catalogues
• Dated data: 1998–2025 (MJD 50944–60969)
• Undated catalogue values: 1,142
• Frequency range of detections: log ν = 7.9–26.2 [Hz] (radio, microwave, infrared, optical, ultraviolet, X-ray, γ-ray)
• Swift measurements analysed by MMDC: 1,436 UVOT and 421 XRT
• Largest catalogues (points): ASAS-SN (2,037), ZTF (1,172), SUFST (732), MMDCOUV (718), MMDCXRT_ORBIT (409)

Data by band

All 7 bands have data. The optical band has the most points, 3,033 of 6,449; its largest catalogue is ASAS-SN with 2,037.

Get the data

• The SED as CSV from the MMDC SED API (docs.mmdc.am).
• In Python, with astro-mmdc:

  from astro_mmdc import MMDC
  sed = MMDC().sed.get(ra=185.38204, dec=28.23292, name="W Comae")

• The interactive SED plot, with time filtering and modeling (needs JavaScript).

Nearby sources

• PG 1218+304, 1.9° away
• B2 1215+30, 2.0° away
• B2 1229+29, 2.3° away
• ON 246, 3.5° away

Other BL Lac objects

• MS 1221.8+2452
• TXS 1221+229
• 1ES 1255+244
• Ton 116
• TXS 1252+224
• 1E 1207.9+3945

How to cite

Sahakyan, N., Vardanyan, V., Giommi, P., et al. 2024, AJ, 168, 289, doi:10.3847/1538-3881/ad8231 (arXiv:2410.01207).