A deep near-infrared view of the Ophiuchus galaxy cluster

Galdeano, D.; Coldwell, G.; Duplancic, F.; Alonso, S.; Pereyra, L.; Minniti, D.; Bacigalupo, R. Zelada; Valotto, C.; Baravalle, L.; Alonso, M. V.; Castellón, J. L. Nilo

doi:10.48550/arxiv.2205.03424

Cited by 2 publications

(3 citation statements)

References 32 publications

(17 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3.1. This result is consistent with what was found by Baravalle et al (2019) and Galdeano et al (2022) for other galaxy clusters studied using the VVV survey.…”

Section: Red Sequencesupporting

confidence: 93%

“…In addition, Baravalle et al (2019) confirmed the existence of the first galaxy cluster, discovered by the VVV survey beyond the galactic disk, by using spectroscopic data from the spectrograph Flamingos 2 (hereafter F2) at Gemini South Observatory. More recently, Galdeano et al (2022) present an NIR view of Ophiuchus, the second-brightest galaxy cluster in the X-ray sky, finding seven times more cluster galaxy candidates than the number of reported Ophiuchus galaxies in previous works.…”

Section: Introductionmentioning

confidence: 84%

See 1 more Smart Citation

Unveiling a new extragalactic structure hidden by the Milky Way

Galdeano

Ferrero

Coldwell

et al. 2022

A&A

View full text Add to dashboard Cite

Context. The zone of avoidance (ZoA) does not allow for clear optical observations of extragalactic sources behind the Milky Way due to the meaningful extinction of the optical emission of these objects. Observations in near-infrared (NIR) wavelengths represent a potential source of astronomical discoveries that support the detection of new galaxies and potentially complete the picture of the large-scale structures in this as-yet poorly explored area of the sky. Aims. Our aim is to decipher the nature of the overdensity located behind the Milky Way in tile b204 of the VISTA Variables in Vía Láctea (VVV) survey. Methods. We studied an area of six arcmin around a galaxy concentration located at l = 354.82 • and b = −9.81 • . We selected five galaxies, taking into account the source distribution on the sky to optimise the requested time for the observations, and we obtained the spectra with Flamingos 2 long-slit spectrograph at Gemini South 8.1-meter telescope. To identify and characterise the absorption features, we fit the galaxies underlying spectrum using the starlight code together with the IRTF stellar library. In addition, the spectroscopic findings are reinforced using complementary photometric techniques such as red-sequence and photometric redshift estimation.Results. The mean spectroscopic redshift estimated from the NIR spectra is z = 0.225 ± 0.014. This value presents a good agreement with that obtained from photometric analysis, photoz = 0.21 ± 0.08, and the probability distribution function of the galaxies in the studied region. Also, the red-sequence slope is consistent with the one expected for NIR observations of galaxy clusters. Conclusions. The redshifts obtained from both, photometric and spectroscopic techniques are in good agreement, allowing for the confirmation of the nature of this structure at z = 0.225 ± 0.014, thereby unveiling a new galaxy cluster, VVVGCl-B J181435-381432, behind the Milky Way bulge.

show abstract

“…3.1. This result is consistent with what was found by Baravalle et al (2019) and Galdeano et al (2022) for other galaxy clusters studied using the VVV survey.…”

Section: Red Sequencesupporting

confidence: 93%

Section: Introductionmentioning

confidence: 84%

Unveiling a new extragalactic structure hidden by the Milky Way

Galdeano

Ferrero

Coldwell

et al. 2022

A&A

View full text Add to dashboard Cite

show abstract

“…3.1. This result is consistent with that found by Baravalle et al (2019) and Galdeano et al (2022) for other galaxy clusters studied using the VVV survey.…”

Section: Red Sequencesupporting

confidence: 93%

Unveiling a new structure behind the Milky Way

Galdeano¹,

Ferrero²,

Coldwell³

et al. 2022

Preprint

View full text Add to dashboard Cite

Context. The ZOA does not allow clear optical observations of extragalactic sources behind the Milky Way due to the meaningful extinction of the optical emission of these objects. The observations in NIR wavelengths represent a potential source of astronomical discoveries supporting the detection of new galaxies, completing the picture of the large scale structure in this still little explored area of the sky. Aims. Our aim is to decipher the nature of the overdensity located behind the Milky Way, in the tile b204 of the VVV survey. Methods. We studied an area of six arcmin around a galaxy concentration located at l = 354.82 • and b = −9.81 • . We selected five galaxies taking into account the source distribution on the sky, in order to optimise the requested time for the observations, and we obtained the spectra with Flamingos 2 long-slit spectrograph at Gemini South 8.1-meter telescope. To identify and characterise the absorption features we have fitted the galaxies underlying spectrum using the starlight code together with the IRTF stellar library. In addition, the spectroscopic findings are reinforced using complementary photometric techniques such as red-sequence and photometric redshift estimation. Results. The mean spectroscopic redshift estimated from the NIR spectra is z = 0.225 ± 0.014. This value presents a good agreement with that obtained from photometric analysis, photoz = 0.21 ± 0.08, and the probability distribution function of the galaxies in the studied region. Also, the red-sequence slope is consistent with the one expected for NIR observations of galaxy clusters. Conclusions. The redshifts obtained from both, photometric and spectroscopic techniques are in good agreement allowing the confirmation of the nature of this structure at z = 0.225 ± 0.014, unveiling a new galaxy cluster, VVVGCl-B J181435-381432, behind the Milky Way bulge.

show abstract

A deep near-infrared view of the Ophiuchus galaxy cluster

Cited by 2 publications

References 32 publications

Unveiling a new extragalactic structure hidden by the Milky Way

Unveiling a new extragalactic structure hidden by the Milky Way

Unveiling a new structure behind the Milky Way

Contact Info

Product

Resources

About