{{Short description|Quasar in the constellation of Boötes}}{{Infobox galaxy|name=B2 1420+32|epoch=[[J2000.0]]|constellation name=[[Boötes]]|ra={{RA|14|22|30.380}}|dec={{DEC|+32|23|10.440}}|z=0.682|h_radial_v=143,130 [[kilometer per second|km/s]]|dist_ly=6.3 billion [[light year|light years]]|image=File:Image of quasar B2 1420+32.png|caption=[[Sloan Digital Sky Survey|SDSS]] image of B2 1420+32 (located center)|appmag_v=19.16|type=FSRQ|names=FBQS J1422+3223, [[Sixth Cambridge Survey of Radio Sources|6C]] 142016+323628, OHIO Q 334, [[Quasar|QSO]] B1420+326, [[Seventh Cambridge Survey|7C]] 142021.30+323647.00, [[ROSAT|RX]] J1422.5+3223, [[NRAO VLA Sky Survey|NVSS]] J142230+322309, PGC 4066234}}
'''B2 1420+32''' also known as '''OQ 334''' and '''QSO B1420+326''', is a [[flat-spectrum radio quasar]]<ref>{{Cite web |title=Multi-band optical observations of the flaring blazar OQ 334 (B2 1420+326) with the new 50cm robotic telescope at IAO |url=https://www.astronomerstelegram.org/?read=16782 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref> in the constellation of [[Boötes]]. Its [[redshift]] is estimated as (z) 0.682 corresponding to a light travel time of 6.3 billion light years<ref>{{Cite journal |last1=Marchini |first1=Alessandro |last2=Bonnoli |first2=Giacomo |last3=Bellizzi |first3=Lorenzo |last4=Millucci |first4=Vincenzo |last5=Paoletti |first5=Riccardo |last6=Stiaccini |first6=Leonardo |last7=Truzzi |first7=Stefano |last8=Ventura |first8=Sofia |last9=Conti |first9=Massimo |last10=Vallerani |first10=Claudio |date=July 2019 |title=The flaring blazar B2 1420+32 below R=14 |url=https://ui.adsabs.harvard.edu/abs/2019ATel12914....1M/abstract |journal=The Astronomer's Telegram |language=en |volume=12914 |pages=1 |bibcode=2019ATel12914....1M }}</ref> and was first detected in March 1973 as a blue stellar object.<ref>{{Cite journal |last1=Bergamini |first1=R. |last2=Bracessi |first2=A. |last3=Colla |first3=G. |last4=Fanti |first4=C. |last5=Ficarra |first5=A. |last6=Formiggini |first6=L. |last7=Gandolfi |first7=E. |last8=Gioia |first8=I. |last9=Lari |first9=C. |last10=Marano |first10=B. |last11=Padrielli |first11=L. |last12=Tomasi |first12=P. |last13=Vigotti |first13=M. |date=March 1973 |title=Optical Identifications of Ra- diosources from the B 2 Catalogue. Quasi Stellar Sources |url=https://articles.adsabs.harvard.edu/pdf/1973A%26A....23..195B |journal=Astronomy and Astrophysics |language=en |volume=23 |pages=195 |bibcode=1973A&A....23..195B |issn=0004-6361}}</ref> This object gained significant attention because of its renewed flaring activity, categorized as changing looking [[blazar]] and is the fourth known distant object displaying very high energy [[Radio wave|radio emission]].
== Description == B2 1420+32 is extremely variable on an [[electromagnetic spectrum]]. A known blazar, it is shown to undergo extreme [[Gamma ray|gamma-ray]] activity in 2018 after a ten-year quiescent period, displaying a three-day flux of 4.79 ± 0.59 averaging a photon index of 1.96 ± 0.10.<ref name=":0">{{Cite journal |last1=Prince |first1=Raj |last2=Khatoon |first2=Rukaiya |last3=Stalin |first3=C. S. |date=April 2021 |title=Broad-band study of OQ 334 during its flaring state |journal=Monthly Notices of the Royal Astronomical Society |language=en |volume=502 |issue=4 |pages=5245–5258 |doi=10.1093/mnras/stab369 |arxiv=2102.03516 |doi-access=free |issn=0035-8711}}</ref> The same year in December, it reached a daily average gamma-ray flux of 1.3 ± 0.2 × 10<sup>−6</sup> [[Photon|photons]] cm<sup>−2</sup> s<sup>−1</sup>, making it 180 times greater than its observed flux in the four year observation period.<ref>{{Cite journal |last=Ciprini |first=Stefano |date=December 2018 |title=Fermi LAT detection of a GeV gamma-ray flare from blazar OQ 334 (B2 1420+32) |url=https://www.astronomerstelegram.org/?read=12277 |journal=The Astronomer's Telegram |language=en |volume=12277 |pages=1 |bibcode=2018ATel12277....1C }}</ref> On December 30 and 31 in 2019, the fluxes were estimated to be 0.9 ± 0.1 × 10<sup>−6</sup> photons cm<sup>−2</sup> s<sup>−1</sup> and 1.7 ± 0.2 × 10<sup>−6</sup> photons cm<sup>−2</sup> s<sup>−1</sup>.<ref>{{Cite journal |last1=Malik |first1=Zahoor |last2=Akbar |first2=Sikandar |last3=Shah |first3=Zahir |last4=Misra |first4=Ranjeev |last5=Dar |first5=Athar A |last6=Manzoor |first6=Aaqib |last7=Ahanger |first7=Sajad |last8=Nazir |first8=Zeeshan |last9=Iqbal |first9=Naseer |last10=Rubab |first10=Seemin |last11=Tantry |first11=Javaid |date=2025-04-15 |title=Statistical Insights into flux and photon index distributions of VHE FSRQs from ''Fermi''-LAT observations |journal=Monthly Notices of the Royal Astronomical Society |volume=539 |issue=3 |pages=2185–2201 |doi=10.1093/mnras/staf620 |doi-access=free |issn=0035-8711}}</ref> Two near-infrared flares were observed from the object displaying a [[K band (infrared)|K-band]] flux of 14.28 ± 0.05 on June 27, 2019, and [[H band (infrared)|H-band]] flux of 12.14 ± 0.03 on March 31, 2023.<ref>{{Cite web |title=A New Large NIR Flare of the blazar HB891420+326 |url=https://www.astronomerstelegram.org/?read=12866 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref><ref>{{Cite journal |last1=Carrasco |first1=L. |last2=Escobedo |first2=G. |last3=Porras |first3=A. |last4=Recillas |first4=E. |last5=Felix |first5=L. |date=April 2023 |title=New Giant NIR flare of the FSRQ HB891420+326 |url=https://ui.adsabs.harvard.edu/abs/2023ATel16021....1C/abstract |journal=The Astronomer's Telegram |language=en |volume=16021 |pages=1 |bibcode=2023ATel16021....1C }}</ref>
During the first month of 2020, B2 1420+32 underwent a high energy powerful gamma-ray flare,<ref>{{Cite web |title=Detection of very-high-energy gamma-ray emission from B2 1420+32 with the MAGIC telescopes |url=https://www.astronomerstelegram.org/?read=13412 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref><ref>{{Cite web |title=A strong optical flaring from the Seyfert 1 Galaxy OQ 334 (B2 1420+326) |url=https://www.astronomerstelegram.org/?read=16681 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref><ref name=":1">{{Cite journal |last1=Acciari |first1=V. A. |last2=Ansoldi |first2=S. |last3=Antonelli |first3=L. A. |last4=Engels |first4=A. Arbet |last5=Artero |first5=M. |last6=Asano |first6=K. |last7=Baack |first7=D. |last8=Babić |first8=A. |last9=Baquero |first9=A. |last10=Almeida |first10=U. Barres de |last11=Barrio |first11=J. A. |last12=González |first12=J. Becerra |last13=Bednarek |first13=W. |last14=Bellizzi |first14=L. |last15=Bernardini |first15=E. |date=2021-03-01 |title=VHE gamma-ray detection of FSRQ QSO B1420+326 and modeling of its enhanced broadband state in 2020 |url=https://www.aanda.org/articles/aa/abs/2021/03/aa39687-20/aa39687-20.html |journal=Astronomy & Astrophysics |language=en |volume=647 |pages=A163 |doi=10.1051/0004-6361/202039687 |arxiv=2012.11380 |bibcode=2021A&A...647A.163M |issn=0004-6361}}</ref> with its radio emission noted as increasing by February.<ref>{{Cite web |title=Continuing flux density increase in OQ 334 revealed by Sardinia Radio Telescope dual-frequency observations |url=https://www.astronomerstelegram.org/?read=13582 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref> In July 2021, it again underwent a flaring period, detected by astronomers at 14 and 7 [[Ammeter|milliammeter]] bands, who happened to observe it as part of the TELAMON program.<ref>{{Cite web |title=Radio Flaring of the Quasar B2 1420+32 |url=https://www.astronomerstelegram.org/?read=14822 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref> Raj Prince noted one of the peaks during its flaring state display the highest known gamma-ray photon level at 77 GeV, indicating the emitting region is either situated on the broad-line region outer boundary or at the [[torus]] inner edge.<ref name=":0" /> DCF analysis, would find the time lags of its light curve is 1.69 days.<ref>{{Cite journal |last1=Xiao |first1=Hu-Bing |last2=Cao |first2=Hai-Tao |last3=Xue |first3=Rui |last4=Cai |first4=Jin-Ting |last5=Wang |first5=Ge-Ge |last6=Manganaro |first6=Marina |last7=Zhang |first7=Shao-Hua |last8=Ouyang |first8=Zhi-Hao |last9=Fu |first9=Li-Ping |last10=Fan |first10=Jun-Hui |date=2024-05-28 |title=Probing the Gamma-Ray Emission Region of Five TeV Flat Spectrum Radio Quasars |journal=Research in Astronomy and Astrophysics |volume=24 |issue=6 |pages=065013 |doi=10.1088/1674-4527/ad420e |bibcode=2024RAA....24f5013X |issn=1674-4527|doi-access=free }}</ref>
Additionally to its extreme gamma-ray activity, B2 1420+32 has optical variability.<ref>{{Cite web |title=ASAS-SN Discovery of an Unprecedented >2 Magnitude Optical Flare from QSO B2 1420+32 |url=https://www.astronomerstelegram.org/?read=11110 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref> As detected on July 30 2021, astronomers from the [[Crimean Astrophysical Observatory]] noted its increasing activity with an [[R band|R-band]] magnitude of 15.156; it previously had an R-band magnitude of 15.50 the previous night.<ref name=":2">{{Cite web |title=B2 1420+32 is in high optical and polarization state |url=https://www.astronomerstelegram.org/?read=14819 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref> A year later on July 31, 2022, it reached 16.13.<ref name=":3">{{Cite web |title=B2 1420+32 is brightening in optical |url=https://www.astronomerstelegram.org/?read=15534 |access-date=2025-07-14 |website=The Astronomer's Telegram}}</ref> The [[linear polarization]] levels also increased from 27.5% to 33.5% in 2021 but decreased to 22.5% in 2022.<ref name=":2" /><ref name=":3" />
The nucleus of B2 1420+32 is constantly [[Active galactic nucleus|active]] due to a presence of its [[accretion disk]] around its [[supermassive black hole]]. The black hole in the center of the object, is estimated to be 4 × 10<sup>8</sup> ''[[Solar mass|M<sub>☉</sub>]]'' based on a virial-based scaling relationship with an accretion disk luminosity of 2 × 10<sup>18</sup> erg s<sup>−1</sup>.<ref>{{Cite journal |last1=Brotherton |first1=Michael S. |last2=Singh |first2=Vikram |last3=Runnoe |first3=Jessie |date=2015-12-21 |title=Orientation and quasar black hole mass estimation |journal=Monthly Notices of the Royal Astronomical Society |volume=454 |issue=4 |pages=3864–3871 |doi=10.1093/mnras/stv2186 |doi-access=free |issn=0035-8711|arxiv=1509.06468 }}</ref><ref name=":1" />
The active galactic nucleus (AGN) of B2 1420+32 can be described as change looking, marked by a series of changes in spectral variability and broad [[Spectral line|emission lines]]. The object is categorized as a flat-spectrum (FSRQ) radio quasar, but flaring activity occurring in January 2018 lead the observers to reclassify it as a [[BL Lacertae object]] (BL Lac).<ref>{{Cite journal |last1=Mishra |first1=Hora D. |last2=Dai |first2=Xinyu |last3=Chen |first3=Ping |last4=Cheng |first4=Jigui |last5=Jayasinghe |first5=T. |last6=Tucker |first6=Michael A. |last7=Vallely |first7=Patrick J. |last8=Bersier |first8=David |last9=Bose |first9=Subhash |last10=Do |first10=Aaron |last11=Dong |first11=Subo |last12=Holoien |first12=Thomas W.-S. |last13=Huber |first13=Mark E. |last14=Kochanek |first14=Christopher S. |last15=Liang |first15=Enwei |date=2021-06-01 |title=The Changing-look Blazar B2 1420+32 |journal=The Astrophysical Journal |volume=913 |issue=2 |pages=146 |doi=10.3847/1538-4357/abf63d |arxiv=2103.08707 |bibcode=2021ApJ...913..146M |doi-access=free |issn=0004-637X}}</ref><ref name=":4">{{Cite web |last1=Nowakowski |first1=Tomasz |last2=Phys.org |title=B2 1420+32 is a changing-look blazar, study finds |url=https://phys.org/news/2021-03-b2-changing-look-blazar.html |access-date=2025-07-14 |website=phys.org |language=en}}</ref> However 96 days later, it has since reverted to back to its original classification of an FSRQ, but since changed again to its BL Lac state after 416 days in July 2019 and so on.<ref name=":5">{{Cite journal |last1=Ren |first1=S. S. |last2=Zhou |first2=R. X. |last3=Zheng |first3=Y. G. |last4=Kang |first4=S. J. |last5=Wu |first5=Q. |date=2024-05-01 |title=The Fermi-LAT view of the changing-look blazar OQ 334 |url=https://www.aanda.org/articles/aa/abs/2024/05/aa47312-23/aa47312-23.html |journal=Astronomy & Astrophysics |language=en |volume=685 |pages=A140 |doi=10.1051/0004-6361/202347312 |arxiv=2402.17099 |bibcode=2024A&A...685A.140R |issn=0004-6361}}</ref><ref>{{Cite journal |last1=Chand |first1=Krishan |last2=Gopal-Krishna |date=2025-05-15 |title=The alternating 'changing-look' blazar OQ 334 (B2 1420+32): new observational clues to the blazar state transitions |journal=Monthly Notices of the Royal Astronomical Society: Letters |volume=541 |issue=1 |pages=L52–L57 |doi=10.1093/mnrasl/slaf053 |doi-access=free |issn=1745-3925}}</ref><ref>{{Cite journal |last1=Ren |first1=S. S. |last2=Zhou |first2=R. X. |last3=Zheng |first3=Y. G. |last4=Kang |first4=S. J. |date=2024-11-01 |title=The Oscillation in Evolution of Changing-look Blazar OQ 334 |journal=The Astrophysical Journal |volume=976 |issue=1 |pages=124 |doi=10.3847/1538-4357/ad83ce |arxiv=2411.08313 |bibcode=2024ApJ...976..124R |doi-access=free |issn=0004-637X}}</ref> This is suggested by changes in its [[Accretion (astrophysics)|accretion]] mode but was later revealed the [[Astrophysical jet|jet]] of B2 1420+32 actually influenced the change in its continuum flux, thus the change of classification between FSRQ and BL Lac.<ref name=":5" /><ref name=":4" />
Polarized intensity radio mapping by [[Very Long Baseline Array]], have showed the source of B2 1420+32 is made up of a bright single radio core situated at the jet's northwestern end, with a weaker extended jet feature located at a position angle of 130°. There is a polarized feature interpreted as a jet knot shown separating from the core. Linear approximation has found the knot is moving at [[superluminal motion]] at speeds of 12.0 ± 1.7c and happens to be ejecting. The polarization direction close to the direction of the jet also suggested the knot might be interpreted as a [[moving shock]].<ref name=":1" />
== References == <references />
== External links == *[http://simbad.u-strasbg.fr/simbad/sim-id?Ident=ICRF%20J142230.3%2B322310 SIMBAD database for B2 1420+32] *[http://atlas.obs-hp.fr/hyperleda/ledacat.cgi?o=B2%201420%2B32 HyperLeda Database for B2 1420+32 (PGC = 4066234)]
{{DEFAULTSORT:B2 1420 32}} [[Category:Quasars]] [[Category:Blazars]] [[Category:Boötes]] [[Category:Active galaxies]] [[Category:BL Lacertae objects]] [[Category:Astronomical objects discovered in 1973]] [[Category:Principal Galaxies Catalogue objects|4066234]]
{{Boötes}}