Transitorische Coxitis

Otte, P.

doi:10.1007/978-3-642-68782-2_4

Cited by 3 publications

(3 citation statements)

References 21 publications

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“…The tight correlation of [S II] and [N II] emission in Figure 7 results in a fairly constant value of [S II]/[N II] over a wide variety of Hα intensities and latitudes in both arms. This result has been seen in numerous studies of the extragalactic WIM analogue, commonly referred to as the diffuse ionized gas (DIG) (Otte & Dettmar 1999;Rand 1998;Wang, Heckman, & Lehnert 1997;Greenawalt, Walterbos, & Braun 1997). As Rand covers in detail, current photoionization models in which variations in [S II]/Hα and [N II]/Hα arise primarily from variations in the ionization parameter (e.g.…”

Section: Discussionmentioning

confidence: 74%

WHAM Observations of Hα, [Sii], and [Nii] toward the Orion and Perseus Arms: Probing the Physical Conditions of the Warm Ionized Medium

Haffner

Reynolds

Tufte

1999

ApJ

218

268

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A large portion of the Galaxy (ℓ = 123 • to 164 • , b = −6 • to −35 • ), which samples regions of the Local (Orion) spiral arm and the more distant Perseus arm, has been mapped with the Wisconsin H-Alpha Mapper (WHAM) in the [S II] λ6716 and [N II] λ6583 lines. By comparing these data with the maps from the WHAM Hα Sky Survey, we begin an investigation of the global physical properties of the Warm Ionized Medium (WIM) in the Galaxy. Several trends noticed in emission-line investigations of diffuse gas in other galaxies are confirmed in the Milky Way and extended to much fainter emission. We find that the [S II]/Hα and [N II]/Hα ratios increase as absolute Hα intensities decrease. For the more distant Perseus arm emission, the increase in these ratios is a strong function of Galactic latitude, b, and thus, of height, z, above the Galactic plane, while the [S II]/[N II] ratio is relatively independent of Hα intensity. Scatter in this ratio appears to be physically significant, and maps of [S II]/[N II] suggest regions with similar ratios are spatially correlated. The Perseus arm [S II]/[N II] ratio is systematically lower than Local emission by 10%-20%. With [S II]/[N II] fairly constant over a large range of Hα intensities, the increase of [S II]/Hα and [N II]/Hα with |z| seems to reflect an increase in temperature. Such an interpretation allows us to estimate the temperature and ionization conditions in our large sample of observations. We find that WIM temperatures range from 6,000 K to 9,000 K with temperature increasing from bright to faint Hα emission (low to high [S II]/Hα and [N II]/Hα) respectively. Changes in [S II]/[N II] appear to reflect changes in the local ionization conditions (e.g. the S + /S ++ ratio). We also measure the electron scale height in the Perseus arm to be 1.0 ± 0.1 kpc, confirming earlier, less accurate determinations.

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Section: Discussionmentioning

confidence: 74%

WHAM Observations of Hα, [Sii], and [Nii] toward the Orion and Perseus Arms: Probing the Physical Conditions of the Warm Ionized Medium

Haffner

Reynolds

Tufte

1999

ApJ

218

268

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“…Calzetti et al 1999a), irregular (e.g. Hoopes et al 1996;Otte & Dettmar 1999) and in late-type spirals (e.g. Wang et al 1997), as well as the Milky Way (Reynolds 1985).…”

Section: Uv/ionizing Photon Leakagementioning

confidence: 99%

Panchromatic Study of Nearby Ultraviolet-bright Starburst Galaxies: Implications for Massive Star Formation and High-Redshift Galaxies

Conselice¹,

Gallagher²,

Calzetti³

et al. 2000

The Astronomical Journal

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We present a panchromatic study of nearby starburst galaxies from the ultraviolet to the visible, including narrow band Hα using WIYN and HST data, to determine how star formation processes affect the morphology and integrated fluxes of nearby starbursts. We find the UV/Hα morphology of starbursts tend to differ, although not in a standard or predictable manner. From our sample of six nearby starbursts, three systems show a good correlation between UV and Hα fluxes, but we find differences in UV and Hα morphology between the other three. Occasionally we find systems with well defined H II regions without the corresponding brightness in the UV, and vice-versa. We discuss the likely mechanisms behind these differences which include: starburst ages, dust absorption, stellar energy ejecta through SNe and winds, as well as leakage of UV photons from stellar clusters. We conclude that the large scale morphological features in starbursts are primarily due to both age and absorption from a 'picket fence' dust distribution.We further demonstrate the similarity and differences between these nearby starbursts and high redshift star forming galaxies. The overall morphology of our sample of starbursts changes little between UV and visible wavelengths. If high redshift galaxies are similar to these starbursts, their morphologies should change little between rest-frame UV and optical. We also show that FIR and UV spectral energy distributions and slopes can be used to determine large scale morphological features for extreme starbursts, with the steepest FIR slopes correlating with the most disturbed galaxies.

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“…Deep gorges along the Meuse and its tributaries in southern Belgium, such as the Lesse, likewise created ideal conditions for trapping migrating herds near numerous Upper Paleolithic sites, including the rich Magdalenian site of Chaleux (see Otte 1984) and the multicomponent (Aurignacian-Gravettian-Magdalenian) Trou Magrite (Straus et al 1992;Straus et al 1993). The open-air site of Huccorgne-Hermitage, which yielded horse and mammoth remains associated with Gravettian artifacts such as Gravette and Font-Robert points, and several adjacent cave sites are strategically located where the Mehaigne River cuts through the Hesbaye Plateau to the Meuse, where an ancient, steep-ridged oxbow nearly blocks the gorge (Froment 1980;Straus etal.…”

Section: Tactical Use Of Topographic Features In Huntingmentioning

confidence: 99%

Upper Paleolithic Hunting Tactics and Weapons in Western Europe

Straus¹

1993

Archaeological Papers of the American

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There is extensive evidence of subsistence intensification by Upper Paleolithic people in Europe, particularly based on the records from Spain, France, Belgium, and Germany. In addition to diversifying their subsistence base wherever and whenever possible, Upper Paleolithic hunters made efficient use of landforms and developed new types of weapon-delivery systems to procure large numbers of herd game. In so doing, they seem to have preferentially chosen to inhabit regions with significant hills and valleys. This allowed them to channel game movements and to hinder or trap herds, thereby facilitating mass kills. Specific physical features (rivers, cliffs, gorges, box canyons, blind valleys, etc.) were of proven use especially to late Upper Paleolithic hunters in their planned, scheduled mass kills of such species as horse, reindeer, red deer, bison, and ibex. The most dynamic component of Upper Paleolithic technologies was weaponry. New types of weapon tips, shafts, hafts, and propulsion devices were developed at an everaccelerating rate throughout the Upper Paleolithic and into the Mesolithic, between at least 35,000-40,000 BP and ca. 7000 BP. Ch«losse Hills REINDEER, HORSES, BOVINES, SAIGAS REINDEER, HORSES, BOVINES, SAIGAS a. 8 85 s.

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Transitorische Coxitis

Cited by 3 publications

References 21 publications

WHAM Observations of Hα, [Sii], and [Nii] toward the Orion and Perseus Arms: Probing the Physical Conditions of the Warm Ionized Medium

WHAM Observations of Hα, [Sii], and [Nii] toward the Orion and Perseus Arms: Probing the Physical Conditions of the Warm Ionized Medium

Panchromatic Study of Nearby Ultraviolet-bright Starburst Galaxies: Implications for Massive Star Formation and High-Redshift Galaxies

Upper Paleolithic Hunting Tactics and Weapons in Western Europe

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