Martin, Nicolas F., McConnachie, Alan W., Irwin, Mike, Widrow, Lawrence M., Ferguson, Annette M. N., Ibata, Rodrigo A., ...
We present the discovery of two new dwarf galaxies, Andromeda XXI and Andromeda XXII, located in the surroundings of the Andromeda and Triangulum galaxies (M31 and M33). These discoveries stem from...
The Monitor project: Rotation periods of low-mass stars in M50 (2008)
Irwin, Jonathan, Aigrain, Suzanne, Bouvier, Jerome, Hebb, Leslie, Hodgkin, Simon, Irwin, Mike, ...
We report on the results of a time-series photometric survey of M50 (NGC 2323), a ~130 Myr open cluster, carried out using the CTIO 4m Blanco telescope and Mosaic-II detector as part of the Monitor...
A trio of new Local Group galaxies with extreme properties (2008)
McConnachie, Alan, Huxor, Avon, Martin, Nicolas, Irwin, Mike, Chapman, Scott, Fahlman, Gregory, ...
We report on the discovery of three new dwarf galaxies in the Local Group. These galaxies are found in new CFHT/MegaPrime g,i imaging of the south-western quadrant of M31, extending our extant survey...
Andromeda XVII: A New Low Luminosity Satellite of M31 (2008)
Irwin, Mike, Ferguson, Annette, Huxor, Avon, Tanvir, Nial, Ibata, Rodrigo, Lewis, Geraint
We report the discovery of a new dwarf spheroidal galaxy near M31 based on INT/WFC imaging. The system, Andromeda XVII (And XVII), is located at a projected radius of ~44 kpc from M31 and has a...
. We are working on a project to automate the multi-parameter classification of stellar spectra using Principal Components Analysis (PCA) and Artificial Neural Networks. We present here the...
. We are working on a project to automate the multi-parameter classification of stellar spectra using Principal Components Analysis (PCA) and Artificial Neural Networks. We present here the...
Coryn Bailer-Jones, Mike Irwin
We investigate the application of neural networks to the automation of MK spectral classification. The data set for this project consists of a set of over 5000 optical (3800--5200 A) spectra obtained...
Irwin, Jonathan, Hodgkin, Simon, Aigrain, Suzanne, Bouvier, Jerome, Hebb, Leslie, Irwin, Mike, ...
We report on the results of a time-series photometric survey of NGC 2362, carried out using the CTIO 4m Blanco telescope and Mosaic-II detector as part of the Monitor project. Rotation periods were...
Irwin, Jonathan, Aigrain, Suzanne, Hodgkin, Simon, Stassun, Keivan G., Hebb, Leslie, Irwin, Mike, ...
We report the discovery of a low-mass (0.26 +/- 0.02, 0.15 +/- 0.01 Msol) pre-main-sequence eclipsing binary with a 5.3 day orbital period. JW 380 was detected as part of a high-cadence time-resolved...
Deconstructing dwarf galaxies: a Suprime-Cam survey of Andromeda II (2007)
McConnachie, Alan, Arimoto, Nobuo, Irwin, Mike
(Abridged) We present deep, sub-horizontal branch, multi-colour photometry of the Andromeda II dwarf spheroidal (And II dSph) taken with Subaru Suprime-Cam. We identify a red clump population in this...
Galactic halo stellar structures in the Triangulum-Andromeda region (2007)
Martin, Nicolas F., Ibata, Rodrigo A., Irwin, Mike
This letter reports on the Galactic stellar structures that appear in the foreground of our Canada-France-Hawaii-Telecopse/MegaCam survey of the halo of the Andromeda galaxy. We recover the main...
Direct Detection of the Asteroidal YORP Effect (2007)
Lowry, Stephen C., Fitzsimmons, Alan, Pravec, Petr, Vokrouhlický, David, Boehnhardt, Hermann, Taylor, Patrick A., ...
Galactic halo stellar structures in the Triangulum-Andromeda region (2007)
Martin, Nicolas F., Ibata, Rodrigo A., Irwin, Mike
This Letter reports on the Galactic stellar structures that appear in the foreground of our Canada-France-Hawaii-Telecopse/MegaCam survey of the halo of the Andromeda galaxy. We recover the main...
An observational limit on the dwarf galaxy population of the local group (2007)
Whiting, Alan B., Hau, George K. T., Irwin, Mike, Verdugo, Miguel
We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar Observatory Sky Survey and ESO/Science Research...
An observational limit on the dwarf galaxy population of the local group (2007)
Whiting, Alan B., Hau, George K. T., Irwin, Mike, Verdugo, Miguel
We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar Observatory Sky Survey and ESO/Science Research...
The Monitor project: Data processing and lightcurve production (2006)
Irwin, Jonathan, Irwin, Mike, Aigrain, Suzanne, Hodgkin, Simon, Hebb, Leslie, Moraux, Estelle
We have begun a large-scale photometric survey of nearby open clusters and star-forming regions, the Monitor project, aiming to measure time-series photometry for >10,000 cluster members over >10...
The Monitor project: Searching for occultations in young open clusters (2006)
Aigrain, Suzanne, Hodgkin, Simon, Irwin, Jonathan, Hebb, Leslie, Irwin, Mike, Favata, Fabio, ...
The Monitor project is a photometric monitoring survey of nine young (1-200Myr) clusters in the solar neighbourhood to search for eclipses by very low mass stars and brown dwarfs and for planetary...
An Observational Limit on the Dwarf Galaxy Population of the Local Group (2006)
Whiting, Alan B., Hau, George K. T., Irwin, Mike, Verdugo, Miguel
We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar survey (POSS-II) and ESO/SRC survey plates and...
The stellar content of the isolated transition dwarf galaxy DDO210 (2006)
McConnachie, Alan W., Arimoto, Nobuo, Irwin, Mike, Tolstoy, Eline
We use Subaru Suprime-Cam and VLT FORS1 photometry of the dwarf galaxy DDO210 to study the global stellar content and structural properties of a transition-type galaxy (with properties intermediate...
Ibata, Rodrigo, Chapman, Scott, Irwin, Mike, Lewis, Geraint, Martin, Nicolas
We present a spectroscopic survey of the newly-discovered Canes Venatici dwarf galaxy using the Keck/DEIMOS spectrograph. Two stellar populations of distinct kinematics are found to be present in...
The Monitor project: Rotation of low-mass stars in the open cluster M34 (2006)
Irwin, Jonathan, Aigrain, Suzanne, Hodgkin, Simon, Irwin, Mike, Bouvier, Jerome, Clarke, Cathie, ...
We report on the results of a V and i-band time-series photometric survey of M34 (NGC 1039) using the Wide Field Camera (WFC) on the Isaac Newton Telescope (INT), achieving better than 1% precision...
Resolving the Stellar Outskirts of M31 and M33 (2006)
Ferguson, Annette, Irwin, Mike, Chapman, Scott, Ibata, Rodrigo, Lewis, Geraint, Tanvir, Nial
Many clues about the galaxy assembly process lurk in the faint outer regions of galaxies. The low surface brightnesses of these parts pose a significant challenge for studies of diffuse light, and...
A keck/deimos survey of red giant branch stars in the outskirts of M31 (2006)
Ferguson, Annette M. N., Chapman, Scott, Ibata, Rodrigo, Irwin, Mike, Lewis, Geraint, McConnachie, Alan
Structural parameters for the M31 dwarf spheroidals (2005)
McConnachie, Alan, Irwin, Mike
(Abridged) The projected structures and integrated properties of the Andromeda I, II, III, V, VI, VII and Cetus dwarf spheroidal galaxies are analysed based upon resolved counts of red giant branch...
The satellite distribution of M31 (2005)
McConnachie, Alan, Irwin, Mike
(Abridged) The spatial distribution of the Galactic satellite system plays an important role in Galactic dynamics and cosmology, where its successful reproduction is a key test of simulations of...
A Keck/DEIMOS Kinematic Study of Andromeda IX: dark matter on the smallest galactic scales (2005)
Chapman, Scott C., Ibata, Rodrigo, Lewis, Geraint F., Ferguson, Annette M. N., Irwin, Mike, McConnachie, Alan, ...
We present the results of a kinematic survey of the dwarf spheroidal satellite of M31, And-IX, which appears to be the lowest surface brightness and also the faintest galaxy (M_V = -8.3) found to...
A Minor Axis Surface Brightness Profile for M31 (2005)
Irwin, Mike, Ferguson, Annette, Ibata, Rodrigo, Lewis, Geraint, Tanvir, Nial
We use data from the Isaac Newton Telescope Wide Field Camera survey of M31 to determine the surface brightness profile of M31 along the south-east minor axis. We combine surface photometry and faint...
The Stellar Populations of M31 Halo Substructure (2005)
Ferguson, Annette, Johnson, Rachel, Faria, Daniel, Irwin, Mike, Ibata, Rodrigo, Johnston, Kathryn, ...
We present the first results from our survey of stellar substructure in the outskirts of M31 using the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope. We discuss the stellar...
A Keck/Deimos Survey of Red Giant Branch Stars in the Outskirts of M31 (2004)
Ferguson, Annette, Chapman, Scott, Ibata, Rodrigo, Irwin, Mike, Lewis, Geraint, McConnachie, Alan
We are using the DEIMOS multi-object spectrograph on the Keck II 10m telescope to conduct a spectroscopic survey of red giant branch stars in the outskirts of M31. To date, velocities have been...
Determining the structure of M31`s giant tidal stream (2004)
McConnachie, Alan, Irwin, Mike, Ibata, Rodrigo, Ferguson, Annette, Lewis, Geraint, Tanvir, Nial
National Nuclear Security Administration under Contract DE-AC04-94AL85000. (2004)
Mike Hightower, Louis Gritzo, Anay Luketa-hanlin, John Covan, Sheldon Tieszen, Mike Irwin, ...
Sandia is a multiprogram laboratory operated by Sandia Corporation,
CIV Absorbers in z>4 Quasars: Tracing Early Galactic Halos Evolution (2003)
Peroux, Celine, Petitjean, Patrick, Aracil, Bastien, Irwin, Mike, McMahon, Richard
We use 29 z>4 quasar spectra to build a homogeneous sample of high-redshift CIV absorbers. We use these data to calculate the number density, n(z), of W_rest(CIV)>0.30 A CIV doublets. We find that...
Kinematic outliers in the LMC: constraints on star-star microlensing (2002)
Zhao, HongSheng, Ibata, Rodrigo, Lewis, Geraint, Irwin, Mike
Although a decade of microlensing searches towards the Large Magellanic Cloud (LMC) has detected 13-25 possible microlensing events, the nature and the location of the lenses, being either halo...
An Optical Velocity for the Phoenix Dwarf Galaxy (2002)
We present the results of a VLT observing program carried out in service mode using FORS1 on ANTU in Long Slit mode to determine the optical velocities of nearby low surface brightness galaxies. As...
Evidence for Stellar Substructure in the Halo and Outer Disk of M31 (2002)
Ferguson, Annette, Irwin, Mike, Ibata, Rodrigo, Lewis, Geraint, Tanvir, Nial
We report the discovery of significant stellar substructure in the halo and outer disk of our nearest large galactic neighbour, M31. Our deep panoramic survey with the Isaac Newton Telescope Wide...
The Southern Dwarf Hunt: Local Group Dwarf Candidates in the Southern Sky (2002)
Whiting, Alan B., Hau, G. K. T., Irwin, Mike
We present observations of 82 Local Group dwarf galaxy candidates, of which 62 were chosen visually from ESO-SRC survey plates of the southern sky (32 of which were not previously catalogued) and the...
The southern dwarf hunt: local group dwarf candidates in the southern sky (2002)
Whiting, Alan B., Hau, George K. T., Irwin, Mike
We present observations of 82 Local Group dwarf galaxy candidates, of which 62 were chosen visually from ESO-SRC survey plates of the southern sky (32 of which were not previously cataloged) and the...
The southern dwarf hunt: local group dwarf candidates in the southern sky (2002)
Whiting, Alan B., Hau, George K. T., Irwin, Mike
We present observations of 82 Local Group dwarf galaxy candidates, of which 62 were chosen visually from ESO-SRC survey plates of the southern sky (32 of which were not previously cataloged) and the...
Hambly, Nigel, Irwin, Mike, MacGillivray, Harvey
In this, the second in a series of three papers concerning the SuperCOSMOS Sky Survey, we describe the methods for image detection, parameterisation, classification and photometry. We demonstrate the...
The SuperCOSMOS Sky Survey. Paper III: Astrometry (2001)
Hambly, Nigel, Davenhall, Clive, Irwin, Mike, MacGillivray, Harvey
In this, the third in a series of three papers concerning the SuperCOSMOS Sky Survey, we describe the astrometric properties of the database. We describe the algorithms employed in the derivation of...
Cosmological Evolution of the Universe Neutral Gas Mass Measured by Quasar Absorption Systems (2001)
Peroux, Celine, McMahon, Richard G., Irwin, Mike, Storrie-Lombardi, Lisa J.
The cosmological evolution of neutral hydrogen is an efficient way of tracing structure formation with redshift. It indicates the rate of evolution of gas into stars and hence the gas consumption and...
Absorption Systems in the Spectra of 66 z > 4 Quasars (2001)
Peroux, Celine, Storrie-Lombardi, Lisa J., McMahon, Richard G., Irwin, Mike, Hook, Isobel M.
We present high signal-to-noise, 5 A resolution (FWHM) spectra of 66 z \ga 4 bright quasars obtained with the 4 m Cerro Tololo Inter-American Observatory and 4.2 m William Hershel telescopes. The...
Hightower, Mike, Gritzo, Louis, Luketa-Hanlin, Anay, Covan, John, Tieszen, Sheldon, Wellman, Gerry, ...
While recognized standards exist for the systematic safety analysis of potential spills or releases from LNG (Liquefied Natural Gas) storage terminals and facilities on land, no equivalent set of...
Semi-automated Extraction of Digital Objective Prism Spectra (1998)
We describe a method for the extraction of spectra from high dispersion objective prism plates. Our method is a catalogue driven plate solution approach, making use of the Right Ascension and...
Angular correlations between LBQS and APM: Weak Lensing by the Large Scale Structure (1998)
Williams, Liliya L. R., Irwin, Mike
We detect a positive angular correlation between bright, high-redshift QSOs and foreground galaxies. The QSOs are taken from the optically selected LBQS Catalogue, while the galaxies are from the APM...
We investigate the application of neural networks to the automation of MK spectral classification. The data set for this project consists of a set of over 5000 optical (3800-5200 AA) spectra obtained...
Physical Parameterization of Stellar Spectra: The Neural Network Approach (1997)
Irwin, Mike, Gilmore, Gerard, Von Hippel, Ted
We present a technique which employs artificial neural networks to produce physical parameters for stellar spectra. A neural network is trained on a set of synthetic optical stellar spectra to give...
Physical Parameterization of Stellar Spectra: The Neural Network Approach (1997)
Mike Irwin, Gerard Gilmore, Ted Von Hippel
We present a technique which employs artificial neural networks to produce physical parameters for stellar spectra. A neural network is trained on a set of synthetic optical stellar spectra to give...
Semi-automated Extraction of Digital Objective Prism Spectra (1997)
We describe a method for the extraction of spectra from high dispersion objective prism plates. Our method is a catalogue driven plate solution approach, making use of the Right Ascension and...