Optical validation and characterization of Planck PSZ1 sources at the Canary Islands observatories

We have identified new clusters and characterized previously unknown Planck Sunyaev–Zeldovich (SZ) sources from the first Planck catalogue of SZ sources (PSZ1). The results presented here correspond to an optical follow-up observational programme developed during approximately one year (2014) at Roque de los Muchachos Observatory, using the 2.5 m Isaac Newton telescope, the 3.5 m Telescopio Nazionale Galileo, the 4.2 m William Herschel telescope and the 10.4 m Gran Telescopio Canarias. We have characterized 115 new PSZ1 sources using deep optical imaging and spectroscopy. We adopted robust criteria in order to consolidate the SZ counterparts by analysing the optical richness, the 2D galaxy distribution, and velocity dispersions of clusters. Confirmed counterparts are considered to be validated if they are rich structures, well aligned with the Planck PSZ1 coordinate and show relatively high velocity dispersion. Following this classification, we confirm 53 clusters, which means that 46% of this PSZ1 subsample has been validated and characterized with this technique. Sixty-two SZ sources (54% of this PSZ1 subset) remain unconfirmed. In addition, we find that the fraction of unconfirmed clusters close to the galactic plane (at |b| < 25°) is greater than that at higher galactic latitudes (|b| > 25°), which indicates contamination produced by radio emission of galactic dust and gas clouds on these SZ detections. In fact, in the majority of the cases, we detect important galactic cirrus in the optical images, mainly in the SZ target located at low galactic latitudes, which supports this hypothesis.

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Optical validation and characterization of Planck PSZ2 sources at the Canary Islands observatories

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935674 ◽

2019 ◽

Vol 628 ◽

pp. A13 ◽

Cited By ~ 2

Author(s):

A. Streblyanska ◽

A. Aguado-Barahona ◽

A. Ferragamo ◽

R. Barrena ◽

J. A. Rubiño-Martín ◽

...

Keyword(s):

Galaxy Clusters ◽

Velocity Dispersion ◽

First Year ◽

Optical Information ◽

Optical Counterpart ◽

Optical Images ◽

Spectroscopic Information ◽

Imaging And Spectroscopy ◽

Most Probable Explanation

Aims. The second catalogue of Planck Sunyaev–Zeldovich (SZ) sources, hereafter PSZ2, is the largest sample of galaxy clusters selected through their SZ signature in the full sky. At the time of publication, 21% of these objects had no known counterpart at other wavelengths. Using telescopes at the Canary Island observatories, we conducted the long-term observational programme 128-MULTIPLE-16/15B (hereafter LP15), a large and complete optical follow-up campaign of all the unidentified PSZ2 sources in the northern sky, with declinations above −15° and no correspondence in the first Planck catalogue PSZ1. The main aim of LP15 is to validate all those SZ cluster candidates, and to contribute to the characterization of the actual purity and completeness of full Planck SZ sample. In this paper, we describe the full programme and present the results of the first year of observations. Methods. The LP15 programme was awarded 44 observing nights, spread over two years in three telescopes at the Roque de los Muchachos Observatory. The full LP15 sample comprises 190 previously unidentified PSZ2 sources. For each target, we performed deep optical imaging and spectroscopy. Our validation procedure combined this optical information with SZ emission as traced by the publicly available Planck Compton y-maps. The final classification of the new galaxy clusters as optical counterparts of the SZ signal is established according to several quantitative criteria based on the redshift, velocity dispersion, and richness of the clusters. Results. This paper presents the detailed study of 106 objects out of the LP15 sample, corresponding to all the observations carried out during the first year of the programme. We confirmed the optical counterpart for 41 new PSZ2 sources, 31 of them being validated using also velocity dispersion based on our spectroscopic information. This is the largest dataset of newly confirmed PSZ2 sources without any previous optical information. All the confirmed counterparts are rich structures (i.e. they show high velocity dispersion), and are well aligned with the nominal Planck coordinates (i.e. ∼70% of them are located at less than 3′ distance). In total, 65 SZ sources are classified as unconfirmed, 57 of them being due to the absence of an optical over-density, and eight of them due to a weak association with the observed SZ decrement. Most of the sources with no optical counterpart are located at low galactic latitudes and present strong galactic cirrus in the optical images, the dust contamination being the most probable explanation for their inclusion in the PSZ2 catalogue.

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Optical validation and characterisation of Planck PSZ1 sources at the Canary Islands observatories

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037552 ◽

2020 ◽

Vol 638 ◽

pp. A146

Author(s):

R. Barrena ◽

A. Ferragamo ◽

J. A. Rubiño-Martín ◽

A. Streblyanska ◽

A. Aguado-Barahona ◽

...

Keyword(s):

Galaxy Clusters ◽

Gaussian Noise ◽

Velocity Dispersion ◽

Thermal Emission ◽

Isaac Newton ◽

La Palma ◽

Second Year ◽

Imaging And Spectroscopy ◽

Non Gaussian ◽

William Herschel

We report new galaxy clusters previously unknown included in the first Planck Sunyaev–Zeldovich (SZ) sources catalogue, the PSZ1. The results presented here were achieved during the second year of a two-year observational programme, the ITP13, developed at the Roque de los Muchachos Observatory (La Palma, Spain). Using the 2.5 m Isaac Newton telescope, the 3.5 m Telescopio Nazionale Galileo, the 4.2 m William Herschel telescope and the 10.4 m Gran Telescopio Canarias we characterised 75 SZ sources with low SZ significance, SZ S/N < 5.32. We performed deep optical imaging and spectroscopy in order to associate actual galaxy clusters with the SZ Planck source. We adopted robust criteria, based on the 2D spatial distribution, richness, and velocity dispersions to confirm actual optical counterparts up to z < 0.85. The selected systems are confirmed only if they are well aligned with respect to the PSZ1 coordinate and show high richness and high velocity dispersion. In addition, we also inspected the Compton y-maps and SZ significance in order to identify unrealistic detections. Following this procedure, we identify 26 cluster counterparts associated with the SZ emission, which means that only about 35% of the clusters considered in this low S/N PSZ1 subsample are validated. Forty-nine SZ sources (∼65% of this PSZ1 subset) remain unconfirmed. At the end of the ITP13 observational programme, we have studied 256 SZ sources with Dec ≥ −15° (212 of them completely unknown), finding optical counterparts for 152 SZ sources. The ITP13 validation programme has allowed us to update the PSZ1 purity, which is now more refined, increasing from 72% to 83% in the low SZ S/N regime. Our results are consistent with the predicted purity curve for the full PSZ1 catalogue and with the expected fraction of false detections caused by the non-Gaussian noise of foreground signals. We find a strong correlation between the number of unconfirmed sources and the thermal emission of diffuse galactic dust at 857 GHz, thus increasing the fraction of false Planck SZ detections at low galactic latitudes.

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CLINICAL AND HISTOPATHOLOGICAL CHARACTERIZATION OF LUPUS NEPHRITIS IN A TERTIARY HEALTH CENTRE, NORTH-EASTERN NIGERIA: REPORT OF FIVE CASES.

Kanem Journal of Medical Sciences ◽

10.36020/kjms.2021.1509 ◽

2021 ◽

Vol 15 (1) ◽

pp. 1-5

Author(s):

◽

Zarami AB ◽

Yerima A ◽

Lawan M ◽

Pindiga UH ◽

...

Keyword(s):

Lupus Nephritis ◽

Health Centre ◽

Maintenance Hemodialysis ◽

Glomerular Sclerosis ◽

Kidney Size ◽

Disease Case ◽

North Eastern ◽

One Year

Background: Lupus nephritis (LN) is an immune complex glomerulonephritis that complicates up to 40% of SLE patients. A kidney biopsy is required for diagnosis and staging of the disease. Case report: We report a cohort of five patients with LN from a tertiary health facility in northeastern Nigeria. The five patients were all women with age ranging from 26 to 55 years, and eGFR of between 6 to 154ml/minute. Four patients had normal kidney size and were biopsied whereas 1 patient had contracted kidney. Diffuse proliferative LN (Class IV) was seen in two patients while the other two patients had glomerular sclerosis (Class VI). Patients were given induction with methylprednisolone and mycophenolate mofetil (MMF). At one year follow up 2(40%) patients were in remission, 1(20%) was on maintenance hemodialysis and 2(40%) patients had died. Conclusion: Lupus nephritis is a common complication of SLE in northeastern Nigeria. Patients have features of advanced kidney disease at presentation.

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9. CLINICAL AND HISTOPATHOLOGICAL CHARACTERIZATION OF LUPUS NEPHRITIS IN A TERTIARY HEALTH CENTRE, NORTH-EASTERN NIGERIA: REPORT OF FIVE CASES

Kanem Journal of Medical Sciences ◽

10.36020/kjms.2021.1501.009 ◽

2021 ◽

Vol 15 (1) ◽

pp. 73-77

Author(s):

◽

Zarami AB ◽

Yerima A ◽

Lawan M ◽

Pindiga UH ◽

...

Keyword(s):

Lupus Nephritis ◽

Health Centre ◽

Maintenance Hemodialysis ◽

Glomerular Sclerosis ◽

Kidney Size ◽

Disease Case ◽

North Eastern ◽

One Year

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Taurus Tunable Filter: A Flexible Approach to Narrowband Imaging

Publications of the Astronomical Society of Australia ◽

10.1071/as98044 ◽

1998 ◽

Vol 15 (1) ◽

pp. 44-49 ◽

Cited By ~ 50

Author(s):

Joss Bland-Hawthorn ◽

D. Heath Jones

Keyword(s):

Galactic Plane ◽

Interference Filter ◽

Tunable Filter ◽

Narrowband Interference ◽

Flexible Approach ◽

Monochromatic Imaging ◽

Narrowband Imaging ◽

William Herschel

AbstractThe Taurus Tunable Filter (TTF) is a tunable narrowband interference filter covering wavelengths from 6300 Å to the sensitivity drop-off of conventional CCDs (∼9600 Å), although a blue ‘arm’ (4000–6500 Å) is to be added by the end of 1997. The TTF offers monochromatic imaging at the Cassegrain foci of both the Anglo-Australian and William Herschel Telescopes, with an adjustable passband of between 6 and 60 Å. In addition, frequency switching with the TTF can be synchronised with movement of charge (charge shuffling) on the CCD, which has important applications to many astrophysical problems. Here we review the different modes of TTF and suggest their use for follow-up narrowband imaging to the AAO/UKST Galactic Plane Hα Survey.

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J-PLUS: Tools to identify compact planetary nebulae in the Javalambre and southern photometric local Universe surveys

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935700 ◽

2020 ◽

Vol 633 ◽

pp. A123

Author(s):

L. A. Gutiérrez-Soto ◽

D. R. Gonçalves ◽

S. Akras ◽

A. Cortesi ◽

C. López-Sanjuan ◽

...

Keyword(s):

Emission Line ◽

Galactic Halo ◽

Galactic Plane ◽

Planetary Nebulae ◽

Diagnostic Tools ◽

The Novel ◽

Local Universe ◽

Isaac Newton ◽

Diagnostic Diagram

Context. From the approximately 3500 planetary nebulae (PNe) discovered in our Galaxy, only 14 are known to be members of the Galactic halo. Nevertheless, a systematic search for halo PNe has never been performed. Aims. In this study, we present new photometric diagnostic tools to identify compact PNe in the Galactic halo by making use of the novel 12-filter system projects, Javalambre Photometric Local Universe Survey (J-PLUS) and Southern-Photometric Local Universe Survey (S-PLUS). Methods. We reconstructed the Isaac Newton Telescope Photometric Hα Survey of the Northern Galactic Plane diagnostic diagram and propose four new ones using (i) the J-PLUS and S-PLUS synthetic photometry for a grid of photo-ionisation models of halo PNe, (ii) several observed halo PNe, as well as (iii) a number of other emission-line objects that resemble PNe. All colour–colour diagnostic diagrams are validated using two known halo PNe observed by J-PLUS during the scientific verification phase and the first data release (DR1) of S-PLUS and the DR1 of J-PLUS. Results. By applying our criteria to the DR1s (~1190 deg2), we identified one PN candidate. However, optical follow-up spectroscopy proved it to be a H II region belonging to the UGC 5272 galaxy. Here, we also discuss the PN and two H II galaxies recovered by these selection criteria. Finally, the cross-matching with the most updated PNe catalogue (HASH) helped us to highlight the potential of these surveys, since we recover all the known PNe in the observed area. Conclusions. The tools here proposed to identify PNe and separate them from their emission-line contaminants proved to be very efficient thanks to the combination of many colours, even when applied – like in the present work – to an automatic photometric search that is limited to compact PNe.

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