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Dust and star formation in NGC 4449
Get PDFThe low degree of processing of the interstellar medium (ISM) in nearby metal-poor galaxies, such as NGC 4449, allow them to be viewed as local analogues of the first galaxies formed in the Universe. In this work we present a study of dust and star formation in NGC 4449, both on global and local scales. We present the spectral energy distribution (SED) of NGC 4449 from the FUV to the sub-mm. Our analysis of a global optical spectrum of NGC 4449 suggests an early onset of star formation, while our results from a chemical evolution dust model provide an indication of the chemical composition of dust globally. These results were used as constraints in constructing a photoionization and radiative transfer MOCASSIN model of NGC 4449. The presented iterative scheme allowed us to infer a total mass of the youngest stellar population which is likely to reside in the centre, in the SW and in the N of NGC 4449. The derived global recent star formation rate is in good agreement with previous estimates. We conclude that our scheme is a new tool, which is particularly suitable for deriving integrated properties of galaxies. Based on spectroscopic observations from the Spitzer Space Telescope and the Herschel Space Telescope we obtained a detailed view of the ionized regions, the photo-dissociation regions and the dust emission within NGC 4449. Our results suggest a deficit of ionized polycyclic aromatic hydrocarbons (PAHs) near the centre of NGC 4449 and bright [OIII]88 emission dominating the ISM cooling locally. Additionally, we examined a sample of type Ibc supernovae to assess their possible contribution to dust formation in the early Universe. We found that the estimated dust masses are too low to consider type Ibc supernovae as major dust producers
Modeling Interacting Galaxies: NGC 4449 revisited
No full textObserving nearby interacting galaxies is a key to understanding galactic physics provided that we know the spatial and temporal perturbations acting on these galaxies. Thus, we have to know the orbits and the gross internal properties of the galaxies. In order to cope with the related extended parameter space, we developed the code MINGA which combines a genetic algorithm with a fast N-body method. As an example for this method, we present a re-analysis of the prototypical system NGC 4449 which is now based on both, the full HI data cube of the NGC 4449 system and on improved determinations of the galactic orbits within a restricted N-body calculation
Block Card 4449 Secor Road
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: 4449 Secor Road (Toledo, Ohio) | Dwelling | Franklin Park Area (Toledo, Ohio) | End Gabled | Dutch Colonial Styl
Studi Komparasi Sni 01-4449-2006 Dengan Jis a 5905 : 2003 .
Get PDFJapan and Indonesia has own criteria in determinating the applicable standards for fiberboard in accordance with the development of industry in each country. JIS and SNI have differences and similarities that are only applicable in their respective countries so that the necessary information to evaluate these standards in order to be valid not only in each country. The purpose of this research is to compare SNI 01-4449-2006 with JIS A 5905-2003. Data analysis was done by using descriptive comparative technic that is compare standards specified in SNI 01-4449-2006 with JIS A 5905-2003 so that known differences and similarities of each standard. Result of the comparition between the parameter of JIS A 5905-2003 and SNI 01-4449-2006 show that the overall standard is different. The difference between these two standardsis available on the parameters of normative parameters of mold thickness, length and width, provided that te testing and measurement of test samples. JIS A 5905-2003has testing standards for fire resistance test and resistance for weather and SNI 01-4449-2006 doesn't have that testing standards. Based of the comparition of the parameters between JIS A 5905-2003 and SNI 01-4449-2006, it can be concluded that JIS A 5905-2003is more complete than SNI 01-4449-2006
GMRT radio continuum study of Wolf–Rayet galaxies – I. NGC 4214 and NGC 4449
No full textWe report low-frequency observations of Wolf–Rayet galaxies, NGC 4214 and NGC 4449 at 610, 325 and 150 MHz, using the Giant Meterwave Radio Telescope (GMRT). We detect diffuse extended emission from NGC 4214 at and NGC 4449. NGC 4449 is observed to be five times more radio luminous than NGC 4214, indicating vigorous star formation. We estimate synchrotron spectral index after separating the thermal free–free emission and obtain αnt = −0.63 ± 0.04 (S∝ναnt) for NGC 4214 and −0.49 ± 0.02 for NGC 4449. About 22 per cent of the total radio emission from NGC 4214 and ∼9 per cent from NGC 4449 at 610 MHz is thermal in origin. We also study the spectra of two compact star-forming regions in NGC 4214 from 325 MHz to 15 GHz and obtain αnt = −0.32 ± 0.02 for NGC 4214-I and αnt = −0.94 ± 0.12 for NGC 4214-II. The luminosities of these star-forming regions (∼1019 WHz−1) appear to be similar to those in circumnuclear rings in normal disc galaxies observed with similar linear resolution. We detect the supernova remnant SNR J1228+441 in NGC 4449 and estimate the spectral index of the emission between 325 and 610 MHz to be −1.8 in the epoch 2008–2009. The galaxies follow the radio–FIR correlation slopes suggesting that star formation in Wolf–Rayet galaxies, which are low-metallicity systems, are similar to that of normal disc galaxies
Studi Komparasi SNI 01-4449-2006 dengan JIS A 5905 : 2003 Papan Serat
No full textJapan and Indonesia has own criteria in determinating the applicable
standards for fiberboard in accordance with the development of industry in each
country. JIS and SNI have differences and similarities that are only applicable in
their respective countries so that the necessary information to evaluate these
standards in order to be valid not only in each country.
The purpose of this research is to compare SNI 01-4449-2006 with JIS A
5905-2003. Data analysis was done by using descriptive comparative technic that
is compare standards specified in SNI 01-4449-2006 with JIS A 5905-2003 so that
known differences and similarities of each standard. Result of the comparition
between the parameter of JIS A 5909-2003 and SNI 01-4449-2006 show that the
overall standard is different. The difference between these two standardsis
available on the parameters of normative parameters of mold thickness, length
and width, provided that te testing and measurement of test samples. JIS A 5909-
2003has testing standards for fire resistance test and resistance for weather and
SNI 01-4449-2006 doesn’t have that testing standards. Based of the comparition
of the parameters between JIS A 5909-2003 and SNI 01-4449-2006, it can be
concluded that JIS A 5909-2003is more complete than SNI 01-4449-2006.43 HalamanSkripsi Sarjan
Η εφαρμογή των διατάξεων του Ν. 4449/2017 στις επιτροπές ελέγχου σύμφωνα με τον κανονισμό 537/2014 του ευρωπαϊκού κοινοβουλίου
No full textΤο αντικείμενο της εργασίας που εξετάζουμε είναι οι αλλαγές που επιφέρει η ισχύς του νόμου 4449/2017, «Υποχρεωτικός έλεγχος των ετήσιων και ενοποιημένων χρηματοοικονομικών καταστάσεων, δημόσια εποπτεία επί του ελεγκτικού έργου και λοιπές διατάξεις» (ΦΕΚ Αρ. Φύλλου 7/24.1.2017), στην οργάνωση και λειτουργία των επιτροπών ελέγχου και ειδικότερα η εφαρμογή των διατάξεων του άρθρου 44 «Επιτροπή Ελέγχου» του παραπάνω νόμου που τέθηκε σε ισχύ στις 24 Ιανουαρίου 2017.
Ο νόμος αυτός βασίζεται στην Οδηγία 2014/56/ΕΚ του Ευρωπαϊκού Κοινοβουλίου και του Συμβουλίου της 16ης Απριλίου 2014 και του Κανονισμού (ΕΕ) αριθμού 537/2014 του Ευρωπαϊκού Κοινοβουλίου και του Συμβουλίου της 16ης Απριλίου 2014.
Σκοπός της παρούσας εργασίας είναι να αντιληφθούμε κατά πόσο οι ανωτέρω αλλαγές επηρεάζουν τις οντότητες δημοσίου συμφέροντος και να εντοπίσουμε τις διαφορές που επιφέρει η νέα νομοθεσία. Στα πλαίσια της παραπάνω εργασίας συντάχθηκαν και στάλθηκαν ερωτηματολόγια σε εταιρείες με κινητές αξίες εισηγμένες στο Χρηματιστήριο Αθηνών. Μέσα από τη διαδικασία των ερωτηματολογίων συλλέξαμε πληροφορίες, τα αποτελέσματα των οποίων αναλύονται σε ιδιαίτερο κεφάλαιο της παρούσας εργασίας
A tidally distorted dwarf galaxy near NGC 4449
No full textNGC 4449 is a nearby Magellanic irregular starburst galaxy1 with a B-band absolute magnitude of −18 and a prominent, massive, intermediate-age nucleus2 at a distance from Earth of 3.8 megaparsecs (ref. 3). It is wreathed in an extraordinary neutral hydrogen (H I) complex, which includes rings, shells and a counter-rotating core, spanning ~90 kiloparsecs (kpc; refs 1, 4). NGC 4449 is relatively isolated5, although an interaction with its nearest known companion—the galaxy DDO 125, some 40 kpc to the south—has been proposed as being responsible for the complexity of its H I structure6. Here we report the presence of a dwarf galaxy companion to NGC 4449, namely NGC 4449B. This companion has a V-band absolute magnitude of −13.4 and a half-light radius of 2.7 kpc, with a full extent of around 8 kpc. It is in a transient stage of tidal disruption, similar to that of the Sagittarius dwarf7 near the Milky Way. NGC 4449B exhibits a striking S-shaped morphology that has been predicted for disrupting galaxies7, 8 but has hitherto been seen only in a dissolving globular cluster9. We also detect an additional arc or disk ripple embedded in a two-component stellar halo, including a component extending twice as far as previously known, to about 20 kpc from the galaxy’s centre
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