An Extended Emission Line Region around Mrk 1172

AbstractWe serendipitously found an intriguing Extended Emission Line Region (EELR) near the quiescent and massive early-type Mrk 1172, with a projected extension of approximately 14 × 14 kpc. Its irregular shape, high gas content, strong emission lines and proximity to an isolated possible faded quasar raise questions about the ionization of this gas and the nature of this object. Analyzing the stellar population in both objects we observe that the EELR has a dominance of young-intermediate and intermediate stellar populations (200 Myr < t < 1 Gyr) with significant star formation activity, while Mrk 1172 is dominated by old stellar population (t > 5 Gyr). BPT diagnostic diagrams indicate that the gas in the EELR is photoionized by hot massive stars rather than by a hard radiation field or by shocks. Further analysis on abundances of the gas and its kinematics shall be performed to better comprehend the nature of this object and how it is interacting with Mrk 1172.

Download Full-text

Optical long-slit spectroscopy in the cluster Abell S0805

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1833 ◽

2019 ◽

Vol 488 (3) ◽

pp. 3685-3715

Author(s):

P C da Rocha-Poppe ◽

V A Fernandes-Martin ◽

M Faúndez-Abans ◽

M de Oliveira-Abans ◽

G A Silva ◽

...

Keyword(s):

Emission Line ◽

Stellar Population ◽

Spectral Synthesis ◽

Emission Lines ◽

Cluster Galaxy ◽

Nuclear Activity ◽

Star Forming ◽

Line Region ◽

Nitrogen Emission ◽

First Time

ABSTRACT This contribution aims to study the nature (kinematic, nuclear activity, and stellar population) of a sample of 10 galaxies in the poor cluster Abell S0805. As no detailed optical spectroscopy for some members has been published yet, the selected sample makes this study ideal for investigating the properties of the following objects: ESO 104- G(002, 006, 007, 008, 009, 010, 013), Fairall 0187, and PGC (062384, 062391). Our main results were obtained after subtraction of the underlying stellar population with the spectral synthesis code starlight. The residual spectra reveal seven galaxies with only absorption lines [ESO 104- G(002, 007, 008, 009), Fairall 0187 and PGC (062384, 062391)], and three galaxies with emission lines [ESO 104- G(006, 010, 013)]. According to the boundaries in the diagnostic diagrams, the intensities of H α and the low-ionization lines ([N ii] λ6584 Å and [S ii] λλ6716,6731 Å) suggest the following results: (i) the brightest cluster galaxy (ESO 104- G006, an elliptical cD galaxy) shows low-ionization nuclear emission-line region (LINER)-like excitation, quite common in ‘cool core clusters’; (ii) the ESO 104- G010 (‘X-Galaxy’ or ‘Crystal Frog’) shows an excess of the nitrogen emission-line [N ii] λ6584 Å not yet reported. We also suggest this object as a LINER; (iii) the spiral ESO 104- G013 is a star-forming galaxy with typical emission lines. No obvious signs of interaction were observed in this study. The heliocentric velocities agree within 1σ with the most recent values. The stellar population, rotation curves, and velocity dispersions are also discussed for the first time for some objects.

Download Full-text

Gaia-assisted discovery of a detached low-ionisation BAL quasar with very large ejection velocities

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936957 ◽

2020 ◽

Vol 634 ◽

pp. A111 ◽

Cited By ~ 2

Author(s):

J. P. U. Fynbo ◽

P. Møller ◽

K. E. Heintz ◽

J. N. Burchett ◽

L. Christensen ◽

...

Keyword(s):

Emission Line ◽

Absorption Line ◽

Emission Lines ◽

Broad Absorption ◽

Broad Absorption Line ◽

Red Edge ◽

First Case ◽

Bl Lac ◽

Spatially Extended ◽

Extended Emission

We report on the discovery of a peculiar broad absorption line (BAL) quasar identified in our Gaia-assisted survey of red quasars. The systemic redshift of this quasar was difficult to establish because of the absence of conspicuous emission lines. Based on deep and broad BAL troughs of at least Si IV, C IV, and Al III, a redshift of z = 2.41 was established under the assumption that the systemic redshift can be inferred from the red edge of the BAL troughs. However, we observe a weak and spatially extended emission line at 4450 Å that is most likely due to Lyman-α emission, which implies a systemic redshift of z = 2.66 if correctly identified. There is also evidence for the onset of Lyman-α forest absorption bluewards of 4450 Å and evidence for Hα emission in the K band consistent with a systemic redshift of z = 2.66. If this redshift is correct, the quasar is an extreme example of a detached low-ionisation BAL quasar. The BALs must originate from material moving with very large velocities ranging from 22 000 km s−1 to 40 000 km s−1. To our knowledge, this is the first case of a systemic-redshift measurement based on extended Lyman-α emission for a BAL quasar. This method could also be useful in cases of sufficiently distant BL Lac quasars without systemic-redshift information.

Download Full-text

The SAMI Galaxy Survey: reconciling strong emission line metallicity diagnostics using metallicity gradients

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab205 ◽

2021 ◽

Vol 502 (3) ◽

pp. 3357-3373

Author(s):

Henry Poetrodjojo ◽

Brent Groves ◽

Lisa J Kewley ◽

Sarah M Sweet ◽

Sebastian F Sanchez ◽

...

Keyword(s):

Emission Line ◽

Electron Temperature ◽

Gas Phase ◽

Mass Range ◽

Accurate Method ◽

Emission Lines ◽

Mass Relation ◽

Strong Emission ◽

Data Release ◽

Accurate Comparison

ABSTRACT We measure the gas-phase metallicity gradients of 248 galaxies selected from Data Release 2 of the SAMI Galaxy Survey. We demonstrate that there are large systematic discrepancies between the metallicity gradients derived using common strong emission line metallicity diagnostics. We determine which pairs of diagnostics have Spearman’s rank coefficients greater than 0.6 and provide linear conversions to allow the accurate comparison of metallicity gradients derived using different strong emission line diagnostics. For galaxies within the mass range 8.5 < log (M/M⊙) < 11.0, we find discrepancies of up to 0.11 dex/Re between seven popular diagnostics in the metallicity gradient–mass relation. We find a suggestion of a break in the metallicity gradient–mass relation, where the slope shifts from negative to positive, occurs between 9.5 < log (M/M⊙) < 10.5 for the seven chosen diagnostics. Applying our conversions to the metallicity gradient–mass relation, we reduce the maximum dispersion from 0.11 dex/Re to 0.02 dex/Re. These conversions provide the most accurate method of converting metallicity gradients when key emission lines are unavailable. We find that diagnostics that share common sets of emission line ratios agree best, and that diagnostics calibrated through the electron temperature provide more consistent results compared to those calibrated through photoionization models.

Download Full-text

The DIVING3D Project: Analysis of the nuclear region of Early-type Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s174392132000157x ◽

2020 ◽

Vol 15 (S359) ◽

pp. 454-456

Author(s):

T. V. Ricci ◽

J. E. Steiner ◽

R. B. Menezes

Keyword(s):

Emission Lines ◽

H Ii Regions ◽

Sample Type ◽

Early Type ◽

Integral Field Spectroscopy ◽

Project Analysis ◽

Line Region ◽

Field Unit ◽

Integral Field

AbstractIn this work, we present preliminary results regarding the nuclear emission lines of a statistically complete sample of 56 early-type galaxies that are part of the Deep Integral Field Spectroscopy View of Nuclei of Galaxies (DIVING3D) Project. All early type galaxies (ETGs) were observed with the Gemini Multi-Object Spectrograph Integral Field Unit (GMOS-IFU) installed on the Gemini South Telescope. We detected emission lines in 93% of the sample, mostly low-ionization nuclear emission-line region galaxies (LINERs). We did not find Transition Objects nor H II regions in the sample. Type 1 objects are seen in ∼23% of the galaxies.

Download Full-text

Dissecting quasars with the J-PAS narrow-band photometric survey

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320002483 ◽

2019 ◽

Vol 15 (S356) ◽

pp. 12-16

Author(s):

Silvia Bonoli ◽

Giorgio Calderone ◽

Raul Abramo ◽

Jailson Alcaniz ◽

Narciso Benitez ◽

...

Keyword(s):

Emission Line ◽

Wavelength Range ◽

Software Package ◽

Narrow Band ◽

Active Galaxies ◽

Emission Lines ◽

Low Resolution ◽

Strong Emission ◽

Optical Wavelength ◽

Quasar Spectra

AbstractThe J-PAS survey will soon start observing thousands of square degrees of the Northern Sky with its unique set of 56 narrow band filters covering the entire optical wavelength range, providing, effectively, a low resolution spectra for every object detected. Active galaxies and quasars, thanks to their strong emission lines, can be easily identified and characterized with J-PAS data. A variety of studies can be performed, from IFU-like analysis of local AGN, to clustering of high-z quasars. We also expect to be able to extract intrinsic physical quasar properties from the J-PAS pseudo-spectra, including continuum slope and emission line luminosities. Here we show the first attempts of using the QSFit software package to derive the properties for 22 quasars at 0.8 < z < 2 observed by the miniJPAS survey, the first deg2 of J-PAS data obtained with an interim camera. Results are compared with the ones obtained by applying the same software to SDSS quasar spectra.

Download Full-text

IUE Spectra of The by Dra/Flare Star AU Mic

International Astronomical Union Colloquium ◽

10.1017/s0252921100096172 ◽

1983 ◽

Vol 71 ◽

pp. 249-250

Author(s):

C.J. Butler ◽

A.D. Andrews ◽

J.G. Doyle ◽

P.B. Byrne ◽

J.L. Linsky ◽

...

Keyword(s):

Light Curve ◽

Emission Line ◽

Flare Star ◽

Emission Lines ◽

Spectral Variation ◽

Strong Emission ◽

Line Intensities ◽

The Mean ◽

Phase Interval

A coordinated series of ground-based optical and IUE observations of BY Dra variables was undertaken to follow the spectral variation of these stars over one cycle. In the first series 20 LWR and 19 SWP trailed spectra were taken of AU Mic over a three day period 4-6 August 1980 .In Figure 1 we show the mean integrated fluxes for the strong emission lines in the SWP spectra of AU Mic over the observed phase interval of 0.14 to 0.8 together with an approximate V light curve determined by the FES on IUE. From comparison of the emission line intensities and FES magnitudes in Figure 1 several points emerge.

Download Full-text

High Velocity Outflow in the Extended Emission-Line Region of the Seyfert Galaxy NGC 7319

The Astronomical Journal ◽

10.1086/117767 ◽

1996 ◽

Vol 111 ◽

pp. 140 ◽

Cited By ~ 16

Author(s):

Kentaro Aoki ◽

Hiroshi Ohtani ◽

Michitosh Yoshida ◽

George Kosugi

Keyword(s):

Emission Line ◽

High Velocity ◽

Seyfert Galaxy ◽

Line Region ◽

Extended Emission

Download Full-text

Comments on the Detection and Classification of Compact Emission-Line Galaxies

International Astronomical Union Colloquium ◽

10.1017/s0252921100104117 ◽

1979 ◽

Vol 47 ◽

pp. 151-153

Author(s):

T. D. Kinman

Keyword(s):

Emission Line ◽

Emission Lines ◽

Ultraviolet Excess ◽

Strong Emission ◽

The Galaxy ◽

Objective Prism ◽

Emission Line Galaxies

Four methods for finding emission-line galaxies have been compared. Method (a) uses the ultraviolet excess, as found either by filter photography (Haro 1956) or by objective prism spectra (Markarian 1967). glanco (1974) introduced a thin prism with the CTIO Schmidt (1740 Å mm-1 at Hβ) which with IIIa-J plates [Method (b)] gave enough resolution for Smith (1975) and MacAlpine et al. (1977a, 1977b) to detect and classify galaxies by strong emission lines. Following a suggestion by McCarthy that even higher dispersion might be useful, I have used the CTIO Schmidt with [Method (c)] the 4° prism, a GGl+55 filter and IIIa-J emulsion and with [Method (d)] the 10° prism, an RG630 filter and IIIa-F emulsion. These latter give about 400 Å mm-1 at Hβ and Hα respectively which improves the visibility of emission lines against the galaxy continuum so that [0111] 5007 and 4959 and Hβ can be seen on the green plates and Hα and [SII] 6725 can be seen on the red plates.

Download Full-text