Astronomers detect dozens of new quasars and galaxies

April 25, 2017 by Tomasz Nowakowski, Phys.org report

Reduced spectra of the first set of eight quasars and possible quasars discovered in this work, displayed in decreasing order of redshift. The object name and the estimated redshift are indicated at the top left corner of each panel. The blue dotted lines mark the expected positions of the Lyα and N V λ1240 emission lines, given the redshifts. The spectra were smoothed using inverse-variance weighted means over 3 – 9 pixels (depending on the S/N), for display purposes. The bottom panel displays a sky spectrum, as a guide to the expected noise. Credit: Matsuoka et al., 2017.
(Phys.org)—A team of astronomers led by Yoshiki Matsuoka of the National Astronomical Observatory of Japan (NAOJ) has detected a treasure trove of new high-redshift quasars (or quasi-stellar objects) and luminous galaxies. The newly found objects could be very important for our understanding of the early universe. The findings were presented Apr. 19 in a paper published on arXiv.org.

High-redshift quasars and galaxies (at redshift higher than 5.0) are useful probes of the in many respects. They offer essential clues on the evolution of the intergalactic medium, quasar evolution, early supermassive black hole growth, as well as evolution of galaxies through cosmic times. Generally speaking, they enable scientists to study the universe when it looked much different than it does today.

Recently, Matsuoka's team has presented the results from the Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs) project, which uses multi-band photometry data provided by the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) survey. HSC is a wide-field camera installed on the Subaru 8.2 m telescope located at the summit of Maunakea, Hawaii and operated by NAOJ. The researchers selected nearly 50 photometric candidates from the HSC-SSP source catalog and then observed them with spectrographs on the Subaru Telescope and the Gran Telescopio Canarias (GTC), located on the island on the Canary Island of La Palma, Spain.

The observations resulted in the identification of 24 new quasars and eight new at redshift between 5.7 and 6.8.

"We took optical spectra of 48 candidates with GTC/OSIRIS and Subaru/FOCAS, and newly discovered 24 quasars and 8 luminous galaxies at 5.7 < z ≤ 6.8," the paper reads.

According to the study, the newly detected quasars have lower luminosity than most of the previously known high-redshift quasi-stellar objects, in contrast to the new galaxies, which have extremely high luminosity when compared to other galaxies found at similar redshift.

The quasar with the highest redshift (6.8) described in the paper received designation J1429 − 0104, while the one with the lowest redshift (5.92) was named J0903 + 0211. Among the new galaxies, J1628 + 4312 was found at the highest (6.03) and J2237 − 0006 at the lowest (5.77). J2237 − 0006 is also the most luminous newly found galaxy.

Meanwhile, the researchers revealed that the SHELLQs project continues, and more new quasars are being discovered, which will be reported in forthcoming papers.

"Further survey observations and follow-up studies of the identified objects, including the construction of the quasar luminosity function at z ∼ 6, are ongoing," they wrote in the paper.

The authors also noted that they plan to conduct follow-up observations of the newly discovered quasars and at various wavelengths from sub-millimeter/radio to X-ray. Several of these objects have already been observed with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, near-infrared spectrographs on the Gemini telescope, located in Hawaii and the Very Large Telescope (VLT), also in Chile.

Explore further: High-redshift quasar discovered by Pan-STARRS

More information: Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). II. Discovery of 32 Quasars and Luminous Galaxies at 5.7 < z < 6.8, arXiv:1704.05854 [astro-ph.GA] arxiv.org/abs/1704.05854

Abstract
We present spectroscopic identification of 32 new quasars and luminous galaxies discovered at 5.7 < z < 6.8. This is the second in a series of papers presenting the results of the Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs) project, which exploits the deep multi-band imaging data produced by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. The photometric candidates were selected by a Bayesian probabilistic algorithm, and then observed with spectrographs on the Gran Telescopio Canarias and the Subaru Telescope. Combined with the sample presented in the previous paper, we have now identified 64 HSC sources over about 430 deg2, which include 33 high-z quasars, 14 high-z luminous galaxies, 2 [O III] emitters at z ~ 0.8, and 15 Galactic brown dwarfs. The new quasars have considerably lower luminosity (M1450 ~ -25 to -22 mag) than most of the previously known high-z quasars. Several of these quasars have luminous (> 10^(43) erg/s) and narrow (< 500 km/s) Ly alpha lines, and also a possible mini broad absorption line system of N V 1240 in the composite spectrum, which clearly separate them from typical quasars. On the other hand, the high-z galaxies have extremely high luminosity (M1450 ~ -24 to -22 mag) compared to other galaxies found at similar redshift. With the discovery of these new classes of objects, we are opening up new parameter spaces in the high-z Universe. Further survey observations and follow-up studies of the identified objects, including the construction of the quasar luminosity function at z ~ 6, are ongoing.

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Tuxford
1.4 / 5 (9) Apr 25, 2017
the newly detected quasars have lower luminosity than most of the previously known high-redshift quasi-stellar objects, in contrast to the new galaxies, which have extremely high luminosity when compared to other galaxies found at similar redshift.

Very likely the new quasars are much closer to us than the red shift would indicate according to the math fairies assumed interpretation of red shift. If a component of red shift is also produced from light climbing out of a deep gravity well, then these objects would appear more distant than they actually are.
LagomorphZero
5 / 5 (1) Apr 25, 2017
"math fairies" lmao.. science really is magic isn't it?
Chris_Reeve
Apr 25, 2017
This comment has been removed by a moderator.
ursiny33
1 / 5 (3) Apr 25, 2017
These objects are probably older than the predicted birth of the big bang , probably from another universe in space time older than our construction , space is probably trillions of years old , our hydrogen atom based universe of objects are new on the block
barakn
5 / 5 (4) Apr 25, 2017
Don't be fooled by the lack of any mention in the press releases; the observation is far more supported than the people here realize.

See the (partial) list of papers here:

https://arijmaki....-papers/

Ummm... you mean like the last one in the list? "[W]e generate four sets of QSO-galaxy pairs and find there is no evidence for a periodicity at the predicted frequency in log(1+z), or at any other frequency... we find the distribution of projected distance between high redshift QSOs and nearby active galaxies and the distribution of redshifts of those active galaxies are consistent with a distribution of simulated random pairs.... We also analyze the periodicity in redshifts of QSOs, and no periodicity is found in high completeness samples, contrary to the DIR model. These results support that QSOs are not ejected from active galaxies."
https://arxiv.org.../0506366
HannesAlfven
1 / 5 (4) Apr 26, 2017
You've cherry-picked one paper out of a list of hundreds.

http://www.setter...uantized

"Many investigations have been executed with the express intent to disprove Tifft. Remarkably, many ended in confirming his research results."
barakn
5 / 5 (3) Apr 27, 2017
No. You presented at that list as if all the papers in it supported quantized redshifts. The presence of that paper proves otherwise. It was literally the first one I opened, and thus the odds are that there are many other dissenting papers in there.

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