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Puragra Guhathakurta - One of the best experts on this subject based on the ideXlab platform.
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Substructure Along M 31’s Southeast Minor Axis: The Forward Continuation of the Giant Southern Stream
Astrophysics and Space Science Proceedings, 2008Co-Authors: Karoline M Gilbert, Puragra Guhathakurta, Mark A Fardal, Jason S Kalirai, Marla C Geha, J Isler, S R Majewski, J C Ostheimer, Richard J Patterson, D B ReitzelAbstract:We present evidence of substructure along the southeastern Minor Axis of the Andromeda galaxy (M 31) that is likely the forward continuation of M 31’s giant southern stream (GSS). M 31 red giant branch (RGB) stars are separated from foreground Milky Way (MW) dwarf stars using a likelihood method based on photometric and spectroscopic diagnostics. The separation is achieved without using the velocity of the stars, allowing an unbiased study of M 31’s stellar kinematics in eight fields located 9 – 30 kpc from M 31’s center (in projection). The line-of-sight velocity distribution of the 1013 M 31 RGB stars is composed of two components: a broad (hot) component (σsph v = 129 kms-1) which presumably represents M 31’s virialized spheroid, and a narrow (cold) component centered near M 31’s systemic velocity with a velocity dispersion that decreases with increasing radial distance. The spatial and velocity distribution of the cold component is similar to that of the “Southeast shelf” predicted by the orbital model of the progenitor of the GSS presented in [1].
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substructure along m 31 s southeast Minor Axis the forward continuation of the giant southern stream
ASSP, 2008Co-Authors: Karoline M Gilbert, Puragra Guhathakurta, Mark A Fardal, Jason S Kalirai, Marla C Geha, J Isler, S R Majewski, J C Ostheimer, Richard J Patterson, D B ReitzelAbstract:We present evidence of substructure along the southeastern Minor Axis of the Andromeda galaxy (M 31) that is likely the forward continuation of M 31’s giant southern stream (GSS). M 31 red giant branch (RGB) stars are separated from foreground Milky Way (MW) dwarf stars using a likelihood method based on photometric and spectroscopic diagnostics. The separation is achieved without using the velocity of the stars, allowing an unbiased study of M 31’s stellar kinematics in eight fields located 9 – 30 kpc from M 31’s center (in projection). The line-of-sight velocity distribution of the 1013 M 31 RGB stars is composed of two components: a broad (hot) component (σsph v = 129 kms-1) which presumably represents M 31’s virialized spheroid, and a narrow (cold) component centered near M 31’s systemic velocity with a velocity dispersion that decreases with increasing radial distance. The spatial and velocity distribution of the cold component is similar to that of the “Southeast shelf” predicted by the orbital model of the progenitor of the GSS presented in [1].
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stellar kinematics in the complicated inner spheroid of m31 discovery of substructure along the southeastern Minor Axis and its relationship to the giant southern stream
The Astrophysical Journal, 2007Co-Authors: Karoline M Gilbert, Puragra Guhathakurta, Mark A Fardal, Marla C Geha, J Isler, J C Ostheimer, Jasonjot S Kalirai, Steven R Majewski, Richard J PattersonAbstract:We present the discovery of a kinematically cold stellar population along the southeastern Minor Axis of the Andromeda galaxy (M31) that is likely the forward continuation of M31's giant southern stream. This discovery was made during an on-going spectroscopic survey of M31 red giant branch (RGB) stars using the DEIMOS instrument on the Keck II 10 m telescope. Stellar kinematics are investigated in eight fields located 9-30 kpc from M31's center (in projection). A likelihood method based on photometric and spectroscopic diagnostics is used to isolate confirmed M31 RGB stars from foreground Milky Way dwarf stars: for the first time, this is done without using radial velocity as a selection criterion, allowing an unbiased study of M31's stellar kinematics. The radial velocity distribution of the 1013 M31 RGB stars contains two components. The broad (hot) component (σ = 129 km s-1) presumably represents M31's virialized spheroid. A significant fraction (19%) of the population is in a narrow (cold) component centered near M31's systemic velocity, with a velocity dispersion that decreases with increasing radial distance, from σ = 55.5 km s-1 at Rproj = 12 kpc to σ = 10.6 km s-1 (9.5 km s-1 after accounting for measurement error) at Rproj = 18 kpc. The spatial and velocity distribution of the cold component matches that of the "Southeast shelf" predicted by the Fardal et al. orbital model of the progenitor of M31's giant southern stream. The metallicity distribution of the cold component matches that of the giant southern stream but is about 0.2 dex more metal rich than that of the hot spheroidal component. We discuss the implications of our discovery on the interpretation of the intermediate-age spheroid population found in this region in recent ultradeep HST imaging studies.
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a subaru suprime cam survey of m31 s spheroid along the south east Minor Axis 1
arXiv: Astrophysics, 2007Co-Authors: M Tanaka, Masashi Chiba, Puragra Guhathakurta, Yutaka KomiyamaAbstract:We have used Suprime-Cam on the Subaru Telescope to conduct a V - and I-band imaging survey of fields sampling the spheroid of the Andromeda galaxy along its south-east Minor Axis. Our photometric data are deep enough to resolve stars down to the red clump. Based on a large and reliable sample of red giant stars available from this deep wide-field imager, we have derived metallicity distributions vs. radius and a surface brightness profile over projected distances of R = 23–66 kpc from the galaxy’s center. The metallicity distributions across this region shows a clear high mean metallicity and a broad distribution ([Fe/H]∼ −0.6 ± 0.5), and indicates no metallicity gradient within our observed range. The surface brightness profile at R > 40 kpc is found to be flatter than previously thought. It is conceivable that this part of the halo samples as yet unidentified, metal-rich substructure. Subject headings: galaxies: individual (M31) — galaxies: halos — galaxies: structure
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A SUBARU/SUPRIME-CAM SURVEY OF M31'S SPHEROID ALONG THE SOUTH-EAST Minor Axis 1
arXiv: Astrophysics, 2007Co-Authors: M Tanaka, Masashi Chiba, Puragra Guhathakurta, Yutaka KomiyamaAbstract:We have used Suprime-Cam on the Subaru Telescope to conduct a V - and I-band imaging survey of fields sampling the spheroid of the Andromeda galaxy along its south-east Minor Axis. Our photometric data are deep enough to resolve stars down to the red clump. Based on a large and reliable sample of red giant stars available from this deep wide-field imager, we have derived metallicity distributions vs. radius and a surface brightness profile over projected distances of R = 23–66 kpc from the galaxy’s center. The metallicity distributions across this region shows a clear high mean metallicity and a broad distribution ([Fe/H]∼ −0.6 ± 0.5), and indicates no metallicity gradient within our observed range. The surface brightness profile at R > 40 kpc is found to be flatter than previously thought. It is conceivable that this part of the halo samples as yet unidentified, metal-rich substructure. Subject headings: galaxies: individual (M31) — galaxies: halos — galaxies: structure
Yutaka Komiyama - One of the best experts on this subject based on the ideXlab platform.
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a subaru suprime cam survey of m31 s spheroid along the south east Minor Axis 1
arXiv: Astrophysics, 2007Co-Authors: M Tanaka, Masashi Chiba, Puragra Guhathakurta, Yutaka KomiyamaAbstract:We have used Suprime-Cam on the Subaru Telescope to conduct a V - and I-band imaging survey of fields sampling the spheroid of the Andromeda galaxy along its south-east Minor Axis. Our photometric data are deep enough to resolve stars down to the red clump. Based on a large and reliable sample of red giant stars available from this deep wide-field imager, we have derived metallicity distributions vs. radius and a surface brightness profile over projected distances of R = 23–66 kpc from the galaxy’s center. The metallicity distributions across this region shows a clear high mean metallicity and a broad distribution ([Fe/H]∼ −0.6 ± 0.5), and indicates no metallicity gradient within our observed range. The surface brightness profile at R > 40 kpc is found to be flatter than previously thought. It is conceivable that this part of the halo samples as yet unidentified, metal-rich substructure. Subject headings: galaxies: individual (M31) — galaxies: halos — galaxies: structure
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A SUBARU/SUPRIME-CAM SURVEY OF M31'S SPHEROID ALONG THE SOUTH-EAST Minor Axis 1
arXiv: Astrophysics, 2007Co-Authors: M Tanaka, Masashi Chiba, Puragra Guhathakurta, Yutaka KomiyamaAbstract:We have used Suprime-Cam on the Subaru Telescope to conduct a V - and I-band imaging survey of fields sampling the spheroid of the Andromeda galaxy along its south-east Minor Axis. Our photometric data are deep enough to resolve stars down to the red clump. Based on a large and reliable sample of red giant stars available from this deep wide-field imager, we have derived metallicity distributions vs. radius and a surface brightness profile over projected distances of R = 23–66 kpc from the galaxy’s center. The metallicity distributions across this region shows a clear high mean metallicity and a broad distribution ([Fe/H]∼ −0.6 ± 0.5), and indicates no metallicity gradient within our observed range. The surface brightness profile at R > 40 kpc is found to be flatter than previously thought. It is conceivable that this part of the halo samples as yet unidentified, metal-rich substructure. Subject headings: galaxies: individual (M31) — galaxies: halos — galaxies: structure
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the extended star formation history of the andromeda spheroid at 35 kpc on the Minor Axis
The Astrophysical Journal, 2007Co-Authors: Thomas M Brown, Masashi Chiba, Puragra Guhathakurta, Yutaka Komiyama, Karoline M Gilbert, Rachael L Beaton, Henry C Ferguson, Jasonjot S Kalirai, Andreas Koch, Steven R MajewskiAbstract:Using the HST ACS, we have obtained deep optical images reaching well below the oldest main-sequence turnoff in fields on the southeast Minor Axis of the Andromeda galaxy, 35 kpc from the nucleus. These data probe the star formation history in the extended halo of Andromeda—that region beyond 30 kpc that appears both chemically and morphologically distinct from the metal-rich, highly disturbed inner spheroid. The present data, together with our previous data for fields at 11 and 21 kpc, do not show a simple trend toward older ages and lower metallicities, as one might expect for populations further removed from the obvious disturbances of the inner spheroid. Specifically, at 11, 21, and 35 kpc, the mean ages are 9.7, 11.0, and 10.5 Gyr, respectively, and the mean [Fe/H] values are –0.65, –0.87, and –0.98, respectively. In the best-fit model of the 35 kpc population, one-third of the stars are younger than 10 Gyr, whereas only ~10% of the stars are truly ancient and metal-poor. The extended halo thus exhibits clear evidence of its hierarchical assembly, and the contribution from any classical halo formed via early monolithic collapse must be small.
Karoline M Gilbert - One of the best experts on this subject based on the ideXlab platform.
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Substructure Along M 31’s Southeast Minor Axis: The Forward Continuation of the Giant Southern Stream
Astrophysics and Space Science Proceedings, 2008Co-Authors: Karoline M Gilbert, Puragra Guhathakurta, Mark A Fardal, Jason S Kalirai, Marla C Geha, J Isler, S R Majewski, J C Ostheimer, Richard J Patterson, D B ReitzelAbstract:We present evidence of substructure along the southeastern Minor Axis of the Andromeda galaxy (M 31) that is likely the forward continuation of M 31’s giant southern stream (GSS). M 31 red giant branch (RGB) stars are separated from foreground Milky Way (MW) dwarf stars using a likelihood method based on photometric and spectroscopic diagnostics. The separation is achieved without using the velocity of the stars, allowing an unbiased study of M 31’s stellar kinematics in eight fields located 9 – 30 kpc from M 31’s center (in projection). The line-of-sight velocity distribution of the 1013 M 31 RGB stars is composed of two components: a broad (hot) component (σsph v = 129 kms-1) which presumably represents M 31’s virialized spheroid, and a narrow (cold) component centered near M 31’s systemic velocity with a velocity dispersion that decreases with increasing radial distance. The spatial and velocity distribution of the cold component is similar to that of the “Southeast shelf” predicted by the orbital model of the progenitor of the GSS presented in [1].
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substructure along m 31 s southeast Minor Axis the forward continuation of the giant southern stream
ASSP, 2008Co-Authors: Karoline M Gilbert, Puragra Guhathakurta, Mark A Fardal, Jason S Kalirai, Marla C Geha, J Isler, S R Majewski, J C Ostheimer, Richard J Patterson, D B ReitzelAbstract:We present evidence of substructure along the southeastern Minor Axis of the Andromeda galaxy (M 31) that is likely the forward continuation of M 31’s giant southern stream (GSS). M 31 red giant branch (RGB) stars are separated from foreground Milky Way (MW) dwarf stars using a likelihood method based on photometric and spectroscopic diagnostics. The separation is achieved without using the velocity of the stars, allowing an unbiased study of M 31’s stellar kinematics in eight fields located 9 – 30 kpc from M 31’s center (in projection). The line-of-sight velocity distribution of the 1013 M 31 RGB stars is composed of two components: a broad (hot) component (σsph v = 129 kms-1) which presumably represents M 31’s virialized spheroid, and a narrow (cold) component centered near M 31’s systemic velocity with a velocity dispersion that decreases with increasing radial distance. The spatial and velocity distribution of the cold component is similar to that of the “Southeast shelf” predicted by the orbital model of the progenitor of the GSS presented in [1].
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stellar kinematics in the complicated inner spheroid of m31 discovery of substructure along the southeastern Minor Axis and its relationship to the giant southern stream
The Astrophysical Journal, 2007Co-Authors: Karoline M Gilbert, Puragra Guhathakurta, Mark A Fardal, Marla C Geha, J Isler, J C Ostheimer, Jasonjot S Kalirai, Steven R Majewski, Richard J PattersonAbstract:We present the discovery of a kinematically cold stellar population along the southeastern Minor Axis of the Andromeda galaxy (M31) that is likely the forward continuation of M31's giant southern stream. This discovery was made during an on-going spectroscopic survey of M31 red giant branch (RGB) stars using the DEIMOS instrument on the Keck II 10 m telescope. Stellar kinematics are investigated in eight fields located 9-30 kpc from M31's center (in projection). A likelihood method based on photometric and spectroscopic diagnostics is used to isolate confirmed M31 RGB stars from foreground Milky Way dwarf stars: for the first time, this is done without using radial velocity as a selection criterion, allowing an unbiased study of M31's stellar kinematics. The radial velocity distribution of the 1013 M31 RGB stars contains two components. The broad (hot) component (σ = 129 km s-1) presumably represents M31's virialized spheroid. A significant fraction (19%) of the population is in a narrow (cold) component centered near M31's systemic velocity, with a velocity dispersion that decreases with increasing radial distance, from σ = 55.5 km s-1 at Rproj = 12 kpc to σ = 10.6 km s-1 (9.5 km s-1 after accounting for measurement error) at Rproj = 18 kpc. The spatial and velocity distribution of the cold component matches that of the "Southeast shelf" predicted by the Fardal et al. orbital model of the progenitor of M31's giant southern stream. The metallicity distribution of the cold component matches that of the giant southern stream but is about 0.2 dex more metal rich than that of the hot spheroidal component. We discuss the implications of our discovery on the interpretation of the intermediate-age spheroid population found in this region in recent ultradeep HST imaging studies.
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the extended star formation history of the andromeda spheroid at 35 kpc on the Minor Axis
The Astrophysical Journal, 2007Co-Authors: Thomas M Brown, Masashi Chiba, Puragra Guhathakurta, Yutaka Komiyama, Karoline M Gilbert, Rachael L Beaton, Henry C Ferguson, Jasonjot S Kalirai, Andreas Koch, Steven R MajewskiAbstract:Using the HST ACS, we have obtained deep optical images reaching well below the oldest main-sequence turnoff in fields on the southeast Minor Axis of the Andromeda galaxy, 35 kpc from the nucleus. These data probe the star formation history in the extended halo of Andromeda—that region beyond 30 kpc that appears both chemically and morphologically distinct from the metal-rich, highly disturbed inner spheroid. The present data, together with our previous data for fields at 11 and 21 kpc, do not show a simple trend toward older ages and lower metallicities, as one might expect for populations further removed from the obvious disturbances of the inner spheroid. Specifically, at 11, 21, and 35 kpc, the mean ages are 9.7, 11.0, and 10.5 Gyr, respectively, and the mean [Fe/H] values are –0.65, –0.87, and –0.98, respectively. In the best-fit model of the 35 kpc population, one-third of the stars are younger than 10 Gyr, whereas only ~10% of the stars are truly ancient and metal-poor. The extended halo thus exhibits clear evidence of its hierarchical assembly, and the contribution from any classical halo formed via early monolithic collapse must be small.
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the extended star formation history of the andromeda spheroid at twenty one kiloparsecs on the Minor Axis
arXiv: Astrophysics, 2007Co-Authors: Thomas M Brown, Puragra Guhathakurta, Henry C Ferguson, Jasonjot S Kalirai, Ed Smith, Michael R Rich, A Renzini, A V Sweigart, David B Reitzel, Karoline M GilbertAbstract:Using the HST ACS, we have obtained deep optical images of a southeast Minor-Axis field in the Andromeda Galaxy, 21 kpc from the nucleus. In both star counts and metallicity, this field represents a transition zone between the metal-rich, highly-disturbed inner spheroid that dominates within 15 kpc and the metal-poor, diffuse population that dominates beyond 30 kpc. The color-magnitude diagram reaches well below the oldest main-sequence turnoff in the population, allowing a reconstruction of the star formation history in this field. Compared to the spheroid population at 11 kpc, the population at 21 kpc is ~1.3 Gyr older and ~0.2 dex more metal-poor, on average. However, like the population at 11 kpc, the population at 21 kpc exhibits an extended star formation history; one third of the stars are younger than 10 Gyr, although only a few percent are younger than 8 Gyr. The relatively wide range of metallicity and age is inconsistent with a single, rapid star-formation episode, and instead suggests that the spheroid even at 21 kpc is dominated by the debris of earlier merging events likely occurring more than 8 Gyr ago.
Leroy Gardner - One of the best experts on this subject based on the ideXlab platform.
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Stainless steel channel sections under combined compression and Minor Axis bending – part 2: parametric studies and design
Journal of Constructional Steel Research, 2020Co-Authors: Yating Liang, Ou Zhao, Yueling Long, Leroy GardnerAbstract:Abstract Following the experimental study and finite element (FE) model validation described in the companion paper, numerical parametric studies and the evaluation of design provisions for stainless steel channel sections under combined axial compressive load and Minor Axis bending moment are presented herein. The parametric studies were carried out to generate additional structural performance data over a wider range of cross-section aspect ratios and slendernesses, loading combinations and bending orientations. The test data and numerical results have been carefully analysed to develop a comprehensive understanding of the structural performance of stainless steel channel sections under combined compression and Minor Axis bending moment, and to assess the accuracy of the existing design provisions in Europe and North America. Comparisons of ultimate loads from the tests and FE simulations with the codified resistance predictions revealed that the current design standards typically under-estimate the capacity of stainless steel channel sections under combined compression and Minor Axis bending moment; this is attributed primarily to the neglect of material strain hardening and the employment of conservative interaction formulae. Improved design rules featuring more efficient interaction curves, anchored to more precise end points (i.e. cross-section resistances under pure compression and bending moment), are then proposed and presented. The new design proposals are shown to yield both more accurate and more consistent resistance predictions over the existing design provisions. Finally, statistical analyses are presented to confirm the reliability of the new design proposals according to EN 1990.
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Stainless steel channel sections under combined compression and Minor Axis bending – part 1: experimental study and numerical modelling
Journal of Constructional Steel Research, 2020Co-Authors: Yating Liang, Ou Zhao, Yueling Long, Leroy GardnerAbstract:Abstract The local cross-section behaviour of stainless steel channel sections under the combined actions of axial compression and Minor Axis bending moment is investigated in the present paper and its companion paper, based on a comprehensive experimental and numerical study. Two channel section sizes were considered in the experimental programme, with the test specimens laser-welded at the two flange-to-web junctions from hot-rolled EN 1.4307 and EN 1.4404 austenitic stainless steel plates. The experiments involved initial local geometric imperfection measurements and 15 eccentrically loaded stub column (combined loading) tests. The loading eccentricity was varied to achieve a range of ratios of axial compression to Minor Axis bending moment; both orientations of bending (web in compression and web in tension) were considered. The test setup and procedures, together with the key experimental observations, including the load-carrying and deformation capacities, load-end rotation histories and failure modes, are fully reported. A finite element simulation study is then presented, in which the models were first validated against the obtained test results and then employed, in the companion paper, for parametric investigations and the assessment of design provisions.
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stainless steel channel sections under combined compression and Minor Axis bending part 2 parametric studies and design
Journal of Constructional Steel Research, 2019Co-Authors: Yating Liang, Ou Zhao, Yueling Long, Leroy GardnerAbstract:Abstract Following the experimental study and finite element (FE) model validation described in the companion paper, numerical parametric studies and the evaluation of design provisions for stainless steel channel sections under combined axial compressive load and Minor Axis bending moment are presented herein. The parametric studies were carried out to generate additional structural performance data over a wider range of cross-section aspect ratios and slendernesses, loading combinations and bending orientations. The test data and numerical results have been carefully analysed to develop a comprehensive understanding of the structural performance of stainless steel channel sections under combined compression and Minor Axis bending moment, and to assess the accuracy of the existing design provisions in Europe and North America. Comparisons of ultimate loads from the tests and FE simulations with the codified resistance predictions revealed that the current design standards typically under-estimate the capacity of stainless steel channel sections under combined compression and Minor Axis bending moment; this is attributed primarily to the neglect of material strain hardening and the employment of conservative interaction formulae. Improved design rules featuring more efficient interaction curves, anchored to more precise end points (i.e. cross-section resistances under pure compression and bending moment), are then proposed and presented. The new design proposals are shown to yield both more accurate and more consistent resistance predictions over the existing design provisions. Finally, statistical analyses are presented to confirm the reliability of the new design proposals according to EN 1990.
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stainless steel channel sections under combined compression and Minor Axis bending part 1 experimental study and numerical modelling
Journal of Constructional Steel Research, 2019Co-Authors: Yating Liang, Ou Zhao, Yueling Long, Leroy GardnerAbstract:Abstract The local cross-section behaviour of stainless steel channel sections under the combined actions of axial compression and Minor Axis bending moment is investigated in the present paper and its companion paper, based on a comprehensive experimental and numerical study. Two channel section sizes were considered in the experimental programme, with the test specimens laser-welded at the two flange-to-web junctions from hot-rolled EN 1.4307 and EN 1.4404 austenitic stainless steel plates. The experiments involved initial local geometric imperfection measurements and 15 eccentrically loaded stub column (combined loading) tests. The loading eccentricity was varied to achieve a range of ratios of axial compression to Minor Axis bending moment; both orientations of bending (web in compression and web in tension) were considered. The test setup and procedures, together with the key experimental observations, including the load-carrying and deformation capacities, load-end rotation histories and failure modes, are fully reported. A finite element simulation study is then presented, in which the models were first validated against the obtained test results and then employed, in the companion paper, for parametric investigations and the assessment of design provisions.
F Bertola - One of the best experts on this subject based on the ideXlab platform.
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The Mass of Galaxies at Low and High Redshift - Gas Minor-Axis Velocity Gradients in Early-Type Spiral Galaxies
The Mass of Galaxies at Low and High Redshift, 2020Co-Authors: E M Corsini, L Coccato, A Pizzella, F BertolaAbstract:We measured a remarkable gas velocity gradient along the Minor Axis of 5 early-type spiral galaxies. This phenomenon suggests the presence of a kinematically-decoupled component in orthogonal rotation with respect to the galaxy disk. If this is the case a second event has taken place in the history of the galaxy. Alternatively the gas velocity gradient is the result of non-circular motions induced by the potential of a triaxial bulge or of a bar
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Minor Axis velocity gradients in disk galaxies
Astronomy and Astrophysics, 2004Co-Authors: L Coccato, E M Corsini, A Pizzella, L Morelli, F BertolaAbstract:We present the ionized-gas kinematics and photometry of a sample of 4 spiral galaxies which are characterized by a zero-velocity plateau along the major Axis and a velocity gradient along the Minor Axis, respectively. By combining these new kinematical data with those available in the literature for the ionized-gas component of the S0s and spirals listed in the Revised Shapley-Ames Catalog of Bright Galaxies we realized that about 50% of unbarred galaxies show a remarkable gas velocity gradient along the optical Minor Axis. This fraction rises to about 60% if we include unbarred galaxies with an irregular velocity profile along the Minor Axis. This phenomenon is observed all along the Hubble sequence of disk galaxies, and it is particularly frequent in early-type spirals. Since Minor-Axis velocity gradients are unexpected if the gas is moving onto circular orbits in a disk coplanar to the stellar one, we conclude that non-circular and off-plane gas motions are not rare in the inner regions of disk galaxies.
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Minor Axis velocity gradients in spirals and the case of inner polar disks
Astronomy and Astrophysics, 2003Co-Authors: E M Corsini, L Coccato, A Pizzella, F BertolaAbstract:We measured the ionized-gas and stellar kinematics along the major and Minor Axis of a sample of 10 early-type spirals. Much to our surprise we found a remarkable gas velocity gradient along the Minor Axis of 8 of them. According to the kinematic features observed in their ionized-gas velocity fields, we divide our sample galaxies in three classes of objects. (i) NGC 4984, NGC 7213, and NGC 7377 show an overall velocity curve along the Minor Axis without zero-velocity points, out to the last measured radius, which is interpreted as due to the warped structure of the gaseous disk. (ii) NGC 3885, NGC 4224, and NGC 4586 are characterized by a velocity gradient along both major and Minor Axis, although non-zero velocities along the Minor Axis are confined to the central regions. Such gas kinematics have been explained as being due to non-circular motions induced by a triaxial potential. (iii) NGC 2855 and NGC 7049 show a change of slope of the velocity gradient measured along the major Axis (which is shallower in the center and steeper away from the nucleus), as well as non-zero gas velocities in the central regions of the Minor Axis. This has been attributed to the presence of a kinematically-decoupled gaseous component in orthogonal rotation with respect to the galaxy disk, namely an inner polar disk. The case and origin of inner polar disks are discussed and the list of their host galaxies is presented.