An ionized superbubble powered by a protocluster at <i>z</i> = 6.5

We report the results of a pilot spectroscopic program of a region at z = 5.2 in the GOODS-N field containing an overdensity of galaxies around the well-known submillimeter galaxy HDF850.1. We have selected candidate cluster members from the optical 25 medium-band photometric catalog of the project SHARDS (Survey for High-z Absorption Red and Dead Sources). 17 rest-frame UV selected galaxies (LAEs and LBGs) with 5.15<zphot<5.27, candidates to be physically associated with the overdensity, have been observed with the instrument OSIRIS at the GranTeCan telescope. 13 out of these 17 (76 per cent) sources have secure spectroscopic confirmations via the Lyα line at the redshift of the galaxy protocluster PCl−HDF850.1, demonstrating the high reliabilty of our photometric redshift method. 10 out of 13 sources are newly confirmed members. Thus, we increase the number of confirmed members in this overdensity from 13 to 23 objects. In order to fully characterize this structure we combined our dataset with the sample from the literature. Beside the SMG HDF850.1, none of the 23 spectroscopically confirmed members are bright in the far-infrared/submm wavelength regime (SFRIR < few hundred M⊙ yr−1). The clustering analysis of the whole sample of 23 confirmed members reveals four distinct components in physical space in different evolutionary states, within Δz < 0.04 from the central region hosting SMG HDF850.1. The halo mass of the whole structure at z = 5.2, estimated by a variety of methods, range between 2 − 8 × 1012M⊙. The comparison with literature suggests a large scale assembly comparable to the formation of a central Virgo-like cluster at z=0 with several satellite components which will possibly be incorporated in a single halo if the protocluster is the progenitor of a more massive Coma-like cluster (>1015M⊙).

show abstract

Is the Bremer Deep Field reionized, at z ∼ 7?

Espinosa

Más‐Hesse

Calvi

2021

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

This paper shows that the population of star forming galaxies in the Bremer Deep Field (BDF) might have formed two large ionised bubbles. The sources already identified in the BDF have been completed with the expected, non–detected, low luminosity sources at z ∼ 7. We have estimated the number of ionising photons produced per second by the different star forming galaxies in the BDF and have compared it with the number that would be required to reionise the bubbles, taking as reference the ionising emissivities derived from the AMIGA cosmological evolutionary model. In this model we distinguished between single and double reionisation scenarios. We find that with a Lyman continuum escape fraction as low as 10% the two regions we have defined in the BDF would be reionised in the single reionisation scenario, with slightly larger values (up to around 15%) required for the double ionisation case. The rather small values of the escape fraction required to reionise the BDF regions are compatible with the low fraction of Lyα emitters discovered in the BDF, since low values of the Lyα escape fraction would also be expected. Finally, we have noticed that the non–detected low luminosity sources represent the main contribution to the BDF ionising flux.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

hi@scite.ai

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

An ionized superbubble powered by a protocluster at z = 6.5

Cited by 5 publications

References 24 publications

A Lyman-α protocluster at redshift 6.9

A Lyman-α protocluster at redshift 6.9

Probing the existence of a rich galaxy overdensity at z = 5.2

Is the Bremer Deep Field reionized, at z ∼ 7?

Contact Info

Product

Resources

About