Abstracts of talks on Monday March 22nd
Carlos Allende Prieto: APOGEE: H-band multi-object spectroscopy around the Galaxy
The Apache-Point Observatory Galactic Evolution Experiment will
obtain 100,000 high-resolution stellar spectra in the H-band using the SDSS 2.5-m
telescope and a new criogenic spectrograph fed by 300 fibers. Our studies indicate
that with a resolving power of ~ 30,000 and a S/N of ~ 100, the wavelength window
between 1.52 and 1.68 um, will allow us to determine abundances for 15 chemical
elements in cool giants. In this brief overview I will focus on the most interesting
aspects of the APOGEE spectrograph.
Marc Balcells: Introductory talk
ING management, the ING Board, the Science Advisory Committee and the
funding agencies are actively planning the next decade for the
Recent reviews of UK and European astronomy have provided detailed
recommendations to guide this planning.
But it is ultimately the user communities who need to tell us what
they want from the ING.
At this workshop we encourage open discussion of a broad range of
topics such as science priorities, requirements for new instrumentation,
and operational modes.
David Carter: Galaxy clusters
I will be talking about work on clusters of galaxies, including
results from the Coma project, and plans to exploit the HST MCT survey on
Francisco Javier Castander: The PAU narrow-band cosmology survey
The PAU collaboration obtained funding from the Spanish
Consolider-Ingenio 2010 programme in 2007 to lead the implementation of a
world-class experiment to study dark energy. For that purpose it proposed to build a
large area camera to carry out a wide field survey to undertake such study. The main
innovative idea is to use narrow band filters (~100 A wide) covering the optical
spectral range (4500-8500 A) combined with broad band filters to characterise the
spectral energy distribution of all observed objects and thus determine the galaxy
redshifts with photometric techniques with a resolving power equivalent to a low
Janet Drew: Milky Way surveys - IPHAS, UVEX
This talk will identify the nature of these two surveys using the INT/WFC and
briefly discuss the follow-up observations they have and are likely to stimulate.
IPHAS, taking data in r,i,H-alpha is practically complete and is undergoing uniform
calibration currently: UVEX is about one-third of the way through its follow-on
u,g,r,HeI-5876 programme. Applications of these surveys range from the discovery of
very rare object types through to the first comprehensive 3-D extinction mapping of
the Galactic Plane.
Boris Gaensicke: Time domain
Armando Gil de Paz: Studying nearby disk galaxies with MEGARA, the proposed wide-field IFU & MOS for GTC
The current status of MEGARA, the proposed intermediate-spectral
resolution wide-field IFU & MOS for GTC, will be presented. I will focus on the
prospects of MEGARA for the study of stellar populations and kinematics in nearby
disk galaxies. Finally, I will also discuss possible synergies between MEGARA and a
similar but complementary instrument at WHT.
Gerry Gilmore: Galactic archaeology
An outline of the opportunities and context for observing Galaxy
evolution relevant to WHT and INT
Amina Helmi: MOS science on a 4-m telescope
I will discuss the scientific needs for wide-field MOS
in the area of Galactic studies. I will present
a few science cases and the requirements these impose
on the characteristics of the MOS.
Artemio Herrero: Massive star research at WHT
We present a view of our current research on massive stars using the
WHT. The versatility of WHT instrumentation allows us to carry
on this reserach in Galactic and extragalactic objects, at many
different wavelength ranges and combining photometric and spectroscopic
techniques. Nevertheless, there is still room for improvements.
Mike Irwin: Imaging surveys and requirements for spectroscopic follow
up in Galactic Archaeology
Ofer Lahav: Cosmology surveys
Craig Mackay: Diffraction-limited imaging in the visible on the WHT
Adaptive optics techniques have delivered near-diffraction limited
imaging in the near infrared (2.2 ?) but in the visible they have been much less
successful. Faint object diffraction limited imaging in the visible from the ground
has recently been demonstrated on a 5 m telescope with more than twice the
resolution of Hubble for the first time, using a combination of low order AO
correction with Lucky Imaging. A new approach to the design of high efficiency, low
order adaptive curvature sensors which use photon counting CCD detectors will allow
the use of much fainter guide stars to correct much of the atmospheric turbulence.
This approach would allow the 4.2 m WHT to routinely deliver about twice the
resolution of Hubble in the visible for a wide range of astronomical programmes.
The investment required would be relatively small and could be developed relatively
quickly giving the WHT a valuable and unique capability.
Reynier Peletier: Nearby unresolved galaxies with the WHT
In this talk I will discuss a number of ways how the WHT can remain
an important player in the field of nearby unresolved galaxies in the next decade.
Rafael Rebolo: Substellar objects and exoplanets
Huub Rottgering: Follow-up of radio surveys
LOFAR, the Low Frequency Array, is a next-generation radio telescope
that is being built in Northern Europe and expected to be fully
operational at the end of 2010. It will operate at frequencies
from 15 to 240 MHz (corresponding to wavelengths of 20 to 1.2 m). Its
superb sensitivity, high angular resolution, large field of view and
flexible spectroscopic capabilities will represent a dramatic
improvement over previous facilities at these wavelengths. As such,
LOFAR will carry out a broad range of fundamental astrophysical
studies. The design of LOFAR has been driven by four fundamental
astrophysical applications: (i) The Epoch of Reionisation, (ii)
Extragalactic Surveys and their exploitation to study the formation
and evolution of clusters, galaxies and black holes, (iii) Transient
Sources and their association with high energy ob jects such as gamma
ray bursts, and (iv) Cosmic Ray showers and their exploitation to
study the origin of ultra-high energy cosmic rays. During this
contribution we will first present the LOFAR project with an emphasis
on the challenges faced when carrying out sensitive imaging at low
radio frequencies. Subsequently, we will discuss LOFAR's capabilities
to survey the low-frequency radio sky. Main aims for the planned
surveys are studies of z>6 radio galaxies, diffuse emission associated
with distant clusters and starbursting galaxies at z>2. Finally we
will conclude with stressing the importance of the availability
of an efficient MOS redshift machine to accomplish these goals.
Mark Sullivan: WHT and the next generation of wide-field transient surveys
4m-class telescopes are the workhorse facilities for spectroscopic
follow-up of the new, next-generation wide-field transient surveys, such as the
Palomar Transient Factory and PanStarrs-1. The UK has leadership roles in both
these surveys and the UK's access to WHT/ISIS can play a key part in studying the
physics of the transient events located with these surveys. We will discuss our
current ISIS observing strategy and the collaboration between the two survey teams
to maximise the science output of the jointly allocated time. We will show how
queue, flexible, or even robotic observing would increase the productivity, impact,
and timeliness of WHT's future scientific contribution.
Abstracts of posters on Monday March 22nd
Chris Benn, Kevin Dee, Tibor Agocs: ACAM - a new imager/spectrograph for the WHT
ACAM is a new wide-field imager/spectrograph, mounted
permanently at a folded-Cassegrain focus of the 4.2-m William Herschel
Telescope, since summer 2009. It's expected that ACAM will be used for
a broad range of high-impact science programmes requiring rapid
response (e.g. supernovae, gamma-ray bursts), or awkward scheduling
(e.g. exoplanet transits), or the use of specialised filters
(e.g. narrow-band Halpha imaging of low-red shift galaxies). We present
here the optical and mechanical design.
Francisco Javier Castander et al.: The PAU camera
The PAU (Physics of the Accelerating Universe) collaboration is building an
instrument, intended for the William Hershel Telescope prime focus, designed to
perform a large area survey for cosmological studies. The idea is to use an
alternative approach to measure the spectral energy distribution (SED) of galaxies
using narrow band imaging instead of spectroscopy. The SEDs are sampled using ~ 40
filters ~ 100 A wide spanning the optical wavelength range to accurately measure
The FoV is 1 degree, densely populated by 18 state of the art CCDs. The maximum
vignetting is 50% of the focal plane. A pressurized liquid nitrogen tank will feed a
boiler inside the cryostat. The CCD's will be kept at 170K and temperature
homogeneity will be achieved with a coldplate, acting as a heat spreader and thermal
capacitance smoothing the cooling and heating ramps. Low read-out noise of the CCDs
is being prepared using the Monsoon architecture developed by NOAO.
The filters have to be placed as close as possible to the CCD detector surfaces on
segmented exchangeable filter trays. An innovative jukebox-like exchanging mechanism
inside the cryostat based on rolling hybrid bearings technology with tungsten
disulfide as solid lubricant has been chosen to hold the movements inside the
cryostat. Two independent servomotors with absolute encoders outside the cryostat
through magnetic feedthroughs will motion the system.
Maria Luisa Garcia Vargas: Sliced-pupil gratings for
increasing resolution of
We have developed a new concept of gratings that consists
on sandwiching a VPH between two prisms and slicing the pupil, in order to
smooth the angle on the grating, and recovering the image on the detector.
This allows to increase the spectral resolution (by a factor or 2 or 3) of
an already-built instrument without changing the geometrical configuration
either the rest of opto-mechanical components. We are building a prototype
in collaboration with Universidad Complutense in Madrid (already under
manufacturing phase) that will be ready in July 2010. This concept could be
applied to some of the already existent WHT spectrographs.
Garik Israelian: Li and Be abundances in stars with exoplanets
Samantha Rix et al: Visiting instruments at the 4.2-m WHT
The 4.2-m William Herschel Telescope on La Palma is a popular
platform for innovative visiting instruments. Some are geared to specific science programmes,
others extend the explorable 'photon parameter space' beyond that covered
by the WHT's common-user instruments (e.g. by providing high time resolution,
or high polarisation sensitivity).
On average, the WHT hosts
six visiting instruments each semester. We dsecribe some of these below,
and highlight the attractions of bringing new visitor instruments to the
Miguel Santander-Garcia: The AF2 reduction pipeline
We present the pipeline for reducing data from AF2/WYFFOS
(AutoFib2/Wide Field Fibre Optical Spectrograph). This software, written in IDL and
soon available to the public, is able to perform full data reduction (including
fibre to fibre sensitivity corrections and optimal extraction of the individual
spectra) in a broad range of observing strategies. This pipeline will also be
available in an user-friendly, quick-look version to be used at the telescope while
carrying out observations.
Abstracts of talks on Tuesday March 23rd
Tibor Agocs: 2-degree WHT PF optical correctors
I present a conceptual design for two new refractive correctors for
the prime focus of the 4.2m William Herschel Telescope, optimised to
allow multi-object spectroscopy over a two degree field of view. The
proposed designs satisfy the demanding requirement that the PSF be
smaller than 0.5 arcsec (80% encircled energy) over a two degree FOV
and a wavelength range of 380nm - 1000nm. I present the
specifications and describe the design process for the corrector,
which also acts as an atmospheric dispersion corrector (ADC). The
design that I present satisfy the science requirements and forms the
basis of a realistic manufacturable system.
Jeremy Allington-Smith: New ideas for highly-multiplexed spectroscopy
In the last few years, radically new ideas have been put forward for
highly-multiplexed spectroscopy. These include the development of the Diverse Field
Spectroscopy paradigm facilitated by new approaches to fibre bundle fabrication and
the development of efficient optical switching networks. More radical yet is the
Astrophotonics approach which seeks not only the removal of OH lines before
dispersion (as already demonstrated) but also the development of miniaturised
"spectrographs on a chip". Instruments using these ideass may provide exceptional
service not only to WHT observers but also to future observatories using the WHT as
Marco Azzaro: Fiber positioner development for survey instruments
The SIDE group has a valuable experience in fiber positioners for
survey instruments. The group is formed around the collaboration of an industrial
company (AVS) and a research institute (IAA), therefore it offers the unique
capability of developing a product under strict standards both from the scientific
and production/manufacture point of view. Our activity ranges from the design to
fabrication and test of the hardware, electronics and control software.
A prototype positioner is under test at the IAA and some preliminary results on its
performance are already available.
Gavin Dalton: A 1st order VPH-based medium-high resolution spectrograph for WHT-MOS
I will describe a spectrograph design, based on the OPTIMOS-EVE
design for the E-ELT which is perfectly matched to the prime-focus plate scale of
the WHT and would yield high multiplex spectroscopy from R=5000 to R=30000 from a
single spectrograph, working at 1st order with VPH gratings.
David King: Wide-field correctors for WHT: forward-Cassegrain options
Preliminary designs for a 2 degree field f/7 forward cassegrain focus
as a possible alternative to prime focus will be discussed.
Additionally, several spectrograph configurations covering both
high resolution (R~40,000) and low resolution (R~5000) will be
Ray Sharples: Instrumentation for cosmological surveys
I will discuss the instrumentation drivers for cosmological surveys
with 4m-class telescopes and present some new designs for extreme-multiplex
wide-field multi-slit spectrographs on such platforms.
Scott Trager: Specs for a wide-field IFU