1. |
- Jin, Shoko, et al.
(författare)
-
The wide-field, multiplexed, spectroscopic facility WEAVE : Survey design, overview, and simulated implementation
- 2024
-
Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press. - 0035-8711 .- 1365-2966. ; 530:3, s. 2688-2730
-
Tidskriftsartikel (refereegranskat)abstract
- WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, saw first light in late 2022. WEAVE comprises a new 2-deg field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366-959nm at R similar to 5000, or two shorter ranges at . After summarizing the design and implementation of WEAVE and its data systems, we present the organization, science drivers, and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for similar to 3 million stars and detailed abundances for similar to 1.5 million brighter field and open-cluster stars; (ii) survey similar to 0.4 million Galactic-plane OBA stars, young stellar objects, and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey similar to 400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionized gas in z < 0.5 cluster galaxies; (vi) survey stellar populations and kinematics in field galaxies at 0.3 less than or similar to z less than or similar to 0.7; (vii) study the cosmic evolution of accretion and star formation using >1 million spectra of LOFAR-selected radio sources; and (viii) trace structures using intergalactic/circumgalactic gas at z > 2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.
|
|
2. |
- Falcón-Barroso, Jesús, et al.
(författare)
-
A Sauron Study of Stars and Gas in SA Bulges
- 2007
-
Ingår i: Island Universes.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We present results from our ongoing effort to understand the morphological and kinematical properties of early-type galaxies using the integral-field spectrograph SAURON. We discuss the relation between the stellar and gas morphology and kinematics in our sub-sample of 24 representative Sa spiral bulges. We focus on the frequency of kinematically decoupled components and on the presence of star formation in circumnuclear rings.
|
|
3. |
- Fathi, Kambiz, et al.
(författare)
-
Quantifying Resonant Structure in NGC 6946 from Two-dimensional Kinematics
- 2007
-
Ingår i: Astrophysical Journal Letters. ; 667:137
-
Tidskriftsartikel (refereegranskat)abstract
- We study the two-dimensional kinematics of the Hα-emitting gas in the nearby barred Scd galaxy NGC 6946, in order to determine the pattern speed of the primary m=2 perturbation mode. The pattern speed is a crucial parameter for constraining the internal dynamics, estimating the impact velocities of the gravitational perturbation at the resonance radii, and setting up an evolutionary scenario for NGC 6946. Our data allow us to derive the best-fitting kinematic position angle and the geometry of the underlying gaseous disk, which we use to derive the pattern speed using the Tremaine-Weinberg method. We find a main pattern speed ΩPp=22+4-1 km s-1 kpc-1, but our data clearly reveal the presence of an additional pattern speed ΩSp=47+3-2 km s-1 kpc-1 in a zone within 1.25 kpc of the nucleus. Using the epicyclic approximation, we deduce the location of the resonance radii and confirm that inside the outer inner Lindblad resonance radius of the main oval, a primary bar has formed rotating at more than twice the outer pattern speed. We further confirm that a nuclear bar has formed inside the inner Lindblad resonance radius of the primary bar, coinciding with the inner inner Lindblad resonance radius of the large-scale m=2 mode oval.
|
|
4. |
- Peletier, R. F., et al.
(författare)
-
Stars and gas in the inner parts of galaxies seen in SAURON integral field observations
- 2007
-
Ingår i: New Astronomy Reviews. - : Elsevier BV. - 1387-6473. ; 51:1-2, s. 29-33
-
Tidskriftsartikel (refereegranskat)abstract
- We give two examples of spiral galaxies that show non-circular gas motions in the inner kiloparsecs, from SAURON integral field spectroscopy. We use harmonic decomposition of the velocity field of the ionized gas to study the underlying mass distribution, employing linear theory. The higher order harmonic terms and the main kinematic features of the observed data are consistent with an analytically constructed simple bar model. We also present maps of a number of strong absorption lines in M 100, derive simple stellar populations and correlate them with features in the gas kinematics.
|
|
5. |
- Toonen, Silvia, et al.
(författare)
-
The Pattern Speeds of NGC 6946
- 2008
-
Ingår i: Astronomical Society of the Pacific conference series. ; , s. 2-, s. 322-
-
Konferensbidrag (populärvet., debatt m.m.)abstract
- We study the kinematics of the barred spiral galaxy NGC 6946 by investigating the velocity field from Hα Fabry-Perot observations, determine the pattern speed of the bar by using the Tremaine-Weinberg method, and find a main pattern speed of 21.7+4.0-0.8 km-1 s-1 kpc-1. Our data clearly suggest the presence of an additional pattern with a pattern speed more than twice that of the large pattern in this galaxy. We use the epicycle approximation to deduce the location of the resonance radii and subsequently determine the pattern speed between the radii, and find that inside the inner inner Lindblad resonance radius a bar-like system has evolved.
|
|