Near-Infrared and Optical Observations of Galactic Warps

Context. Type Ia Supernovae (SNe Ia) have been used as standardizable candles in the optical wavelengths to measure distances with an accuracy of ~7% out to redshift z ~ 1.5. There is evidence that in the near-infrared (NIR) wavelengths SNe Ia are even better standard candles, however, NIR observations are much more time-consuming. Aims. We aim to test whether the NIR peak magnitudes could be accurately estimated with only a single observation obtained close to maximum light, provided that the time of B band maximum, the B − V color at maximum and the optical stretch parameter are known. Methods. We present multi-epoch UBV RI and single-epoch J and H photometric observations of 16 SNe Ia in the redshift range z = 0.037 − 0.183, doubling the leverage of the current SN Ia NIR Hubble diagram and the number of SNe beyond redshift 0.04. This sample was analyzed together with 102 NIR and 458 optical light curves (LCs) of normal SNe Ia from the literature. Results. The analysis of 45 NIR LCs with well-sampled first maximum shows that a single template accurately describes the LCs if its time axis is stretched with the optical stretch parameter. This allows us to estimate the peak NIR magnitudes of SNe with only few observations obtained within ten days from B-band maximum. The NIR Hubble residuals show weak correlation with ΔM15 and the color excess E(B − V), and for the first time we report a potential dependence on the Jmax − Hmax color. With these corrections, the intrinsic NIR luminosity scatter of SNe Ia is estimated to be ~0.10 mag, which is smaller than what can be derived for a similarly heterogeneous sample at optical wavelengths. Analysis of both NIR and optical data shows that the dust extinction in the host galaxies corresponds to a low RV ≃ 1.8–1.9. Conclusions. We conclude that SNe Ia are at least as good standard candles in the NIR as in the optical and are potentially less affected by systematic uncertainties. We extended the NIR SN Ia Hubble diagram to its nonlinear part at z ~ 0.2 and confirmed that it is feasible to accomplish this result with very modest sampling of the NIR LCs, if complemented by well-sampled optical LCs. With future facilities it will be possible to extend the NIR Hubble diagram beyond redshift z ≃ 1, and our results suggest that the most efficient way to achieve this would be to obtain a single observation close to the NIR maximum.

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Spitzer view of Lyman break galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308018346 ◽

2007 ◽

Vol 3 (S245) ◽

pp. 451-454

Author(s):

Georgios E. Magdis ◽

Dimitra Rigopoulou

Keyword(s):

Rest Frame ◽

Near Infrared ◽

Optical Observations ◽

Spectral Energy ◽

Stellar Content ◽

Mid Infrared ◽

Lyman Break Galaxies ◽

Polycyclic Aromatic ◽

Stellar Masses ◽

First Time

AbstractUsing a combination of deep MID-IR observations obtained by IRAC, MIPS and IRS on board Spitzer we investigate the MID-IR properties of Lyman Break Galaxies (LBGs) at z~3, establish a better understanding of their nature and attempt a complete characterisation of the population. With deep mid-infrared and optical observations of ~1000 LBGs covered by IRAC/MIPS and from the ground respectively, we extend the spectral energy distributions (SEDs) of the LBGs to mid-infrared. Spitzer data reveal for the first time that the mid-infrared properties of the population are inhomogeneous ranging from those with marginal IRAC detections to those with bright rest-frame near-infrared colors and those detected at 24μm MIPS band revealing the newly discovered population of the Infrared Luminous Lyman Break Galaxies (ILLBGs). To investigate this diversity, we examine the photometric properties of the population and we use stellar population synthesis models to probe the stellar content of these galaxies. We find that a fraction of LBGs have very red colors and large estimated stellar masses M∗>5×1010M⊙. We discuss the link between these LBGs and submm-luminous galaxies and we report the detection of rest frame 6.2 and 7.7 μm emission features arising from Polycyclic Aromatic Hydrocarbons (PAH) in the Spitzer/IRS spectrum of an infrared-luminous Lyman break galaxy at z=3.01.

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Tracing Molecular Emission in Spiral Galaxies: The Near Infrared Correspondence

International Astronomical Union Colloquium ◽

10.1017/s0252921100020042 ◽

1994 ◽

Vol 140 ◽

pp. 370-371

Author(s):

R. L. Hurt ◽

J. L. Turner ◽

D. Levine ◽

K. M. Merrill ◽

I. Gatley

Keyword(s):

Large Scale ◽

Near Infrared ◽

Infrared Imaging ◽

Spiral Galaxies ◽

Molecular Structures ◽

Optical Observations ◽

Near Infrared Imaging ◽

Imaging Arrays ◽

Molecular Emission ◽

Infrared Extinction

Near infrared imaging can be a powerful tool in tracing the densest molecular structures in galaxies. The observable molecular emission originates in large molecular cloud complexes which are also subject to significant extinctions caused by the associated dust. It can be difficult to distinguish between regions of moderate and large molecular density with optical observations as both will appear optically thick. Since extinction in the near infrared is only about a tenth of the corresponding visual extinction, multi-band near infrared imaging will trace the regions of the highest optical depths much more effectively. With the advent of large format infrared imaging arrays it is now possible to use infrared extinction maps as a probe of the large scale distribution of molecular emission in extragalactic sources.

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Near-infrared and optical observations of IRAS sources in and near dense cores

The Astrophysical Journal ◽

10.1086/165458 ◽

1987 ◽

Vol 319 ◽

pp. 340 ◽

Cited By ~ 214

Author(s):

P. C. Myers ◽

Gary A. Fuller ◽

R. D. Mathieu ◽

C. A. Beichman ◽

P. J. Benson ◽

...

Keyword(s):

Near Infrared ◽

Optical Observations ◽

Dense Cores

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Near-Infrared and Optical Observations of an Obliquely Viewed Bow Shock: AS 353A/HH 32

The Astrophysical Journal ◽

10.1086/177237 ◽

1996 ◽

Vol 463 ◽

pp. 246 ◽

Cited By ~ 21

Author(s):

Christopher J. Davis ◽

Jochen Eisloeffel ◽

Michael D. Smith

Keyword(s):

Near Infrared ◽

Bow Shock ◽

Optical Observations

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A multi-wavelength classification system for the evolution of star clusters

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316007419 ◽

2015 ◽

Vol 11 (S315) ◽

pp. 142-145

Author(s):

Bradley C. Whitmore ◽

Crystal Brogan ◽

Rupali Chandar ◽

Aaron Evans ◽

John Hibbard ◽

...

Keyword(s):

Classification System ◽

Near Infrared ◽

Infrared Imaging ◽

Cluster Formation ◽

Star Clusters ◽

Radio Continuum ◽

Optical Observations ◽

Small Scale ◽

Molecular Gas ◽

Multi Wavelength

AbstractThe availability of high spatial resolution molecular gas observations from ALMA, and similar resolution observations in the radio continuum using the VLA, is providing the opportunity to make comparisons with specific features seen in optical observations more directly than in the past. Using our ALMA observations of the Antennae galaxies as a springboard, we have compared the locations of small-scale CO (3−2) features with a variety of multi-wavelength observations, in particular optical and near-infrared imaging using both broad (UBVI) and narrow-band data (Hαand Paβ) taken with the HST, and radio (3.6 cm) continuum observations taken with the VLA. This comparison leads to the development of an evolutionary classification system which provides a framework for studying the sequence of star cluster formation and evolution, from diffuse Giant Molecular Clouds (GMCs), to proto, embedded, emerging, young, and intermediate/old star clusters. Using this evolutionary framework, we estimate the maximum age range of clusters formed in a single GMC is approximately 10 Myr. This suggests that the molecular gas is removed over this timescale, resulting in the cessation of star formation and the destruction of the GMC within a radius of about 200 pc.

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Multi-Color Surface Photometry of Nearby Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900128797 ◽

1998 ◽

Vol 179 ◽

pp. 285-286

Author(s):

T. Ichikawa ◽

N. Itoh ◽

K. Yanagisawa

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Near Infrared ◽

Infrared Imaging ◽

Spiral Galaxies ◽

Stellar Structure ◽

Star Formation History ◽

Optical Observations ◽

Wide Field ◽

Formation History

Near-infrared (NIR) emission in galaxies is mainly radiated by old population low temperature stars, which construct the basic stellar structure and keep the trails of past galaxy evolution. On the other hand, optical observations show recent star formation activity, especially in spiral galaxies. Therefore multi-color observations from optical to near-infrared wavelengths are very important to understand the past and recent star-formation history. Nearby large galaxies are well studied not only in optical but also in mid- and far-infrared by IRAS, CO and HI radio observations. However, the study in the near-infrared is still limited because large format arrays are not common. Here we show a wide-field, near-infrared imaging of nearby elliptical and spiral galaxies and discuss their star-formation history.

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Ultraviolet to Near Infrared Observations of BF Cyg

International Astronomical Union Colloquium ◽

10.1017/s0252921100103720 ◽

1988 ◽

Vol 103 ◽

pp. 301-302

Author(s):

A. Cassatella ◽

R. Gonzalez-Riestra ◽

T. Fernandez-Castro ◽

J. Fuensalida ◽

A. Gimenez

Keyword(s):

Canary Islands ◽

Near Infrared ◽

Single Channel ◽

Photon Counting ◽

Optical Observations ◽

Counting System ◽

Infrared Observations ◽

Isaac Newton ◽

Preliminary Results ◽

La Palma

In this paper we provide preliminary results of multifrequency observations of BF Cyg carried out in July 1986. The ultraviolet spectra were obtained on July 26, 1986 using the IUE satellite. The optical observations were made at the Observatorio del Roque de los Muchachos (La Palma, Canary Islands) in July 1986 during the night 13/14 using the Isaac Newton 2.5m telescope with the Intermediate Dispersion Spectrograph (IDS, 500 mm camera) and the Image Photon Counting System (IPCS). The infrared observations were made during the night 13/14 of July, 1986, at the Observatorio del Teide (Tenerife, Canary Islands) using the Carlos Sanchez 1.5m telescope and an infrared single-channel photometer with an InSb detector.

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