An ancient nova shell around the dwarf nova Z Camelopardalis Michael M. Shara, et al. 2007, Nature, Vol. 446 8 March 鹿豹星座.

Slides:

Advertisements

Similar presentations

Summary of Post-Main-Sequence Evolution of Sun-Like Stars M < 4 M sun Fusion stops at formation of C,O core. C,O core becomes degenerate Core collapses;

Advertisements

Lecture 20 White dwarfs.

Lecture 26: The Bizarre Stellar Graveyard: White Dwarfs and Neutron Stars.

How are the lives of stars with close companions different?

Nuclear Interactions in Supernovae By: Alec Fisher 11/14/2012.

PHYS The Main Sequence of the HR Diagram During hydrogen burning the star is in the Main Sequence. The more massive the star, the brighter and hotter.

Star Formation and the Interstellar Medium

Stellar Evolution Chapters 12 and 13. Topics Humble beginnings –cloud –core –pre-main-sequence star Fusion –main sequence star –brown dwarf Life on the.

Shocks Jets and Active Galaxies By Drew Brumm. Shocks Strong Shocks Shocks in accretion –Compact objects –Supernova explosions Accretion of binary systems.

RXTE Observations of Cataclysmic Variables and Symbiotic Stars Koji Mukai NASA/GSFC/CRESST and UMBC.

Fill in the chart when you see a yellow star. Take notes on the stars and events as well.

The Deaths of Stars Chapter 13. The End of a Star’s Life When all the nuclear fuel in a star is used up, gravity will win over pressure and the star will.

Chapter 12 Stellar Evolution. Infrared Image of Helix Nebula.

Supernova. Explosions Stars may explode cataclysmically. –Large energy release (10 3 – 10 6 L  ) –Short time period (few days) These explosions used.

Stars and the HR Diagram Dr. Matt Penn National Solar Observatory

1. accretion disk - flat disk of matter spiraling down onto the surface of a star. Often from a companion star.

The Lives of Stars Chapter 12. Life on Main-Sequence Zero-Age Main Sequence (ZAMS) –main sequence location where stars are born Bottom/left edge of main.

1) Review: main sequence lives of low mass stars Red Giant formation 2) Hotter, more Massive stars CNO cycle nucleosynthesis – creation of the heavier.

Stellar Deaths Novae ans Super Novae 16. Hydrostatic Equilibrium Internal heat and pressure from fusion pushes outward Gravity pulling mass inward Two.

The Deaths of Stars. What Do You Think? Will the Sun someday cease to shine brightly? If so, how will this occur? What is a nova? How does it differ from.

Astronomy Picture of the Day. Recall: Luminosity - Intrinsic property of a star. Apparent Brightness – the brightness we perceive a star to be from Earth.

White Dwarfs PHYS390 Astrophysics Professor Lee Carkner Lecture 17.

Stellar Structure Section 6: Introduction to Stellar Evolution Lecture 17 – AGB evolution: … MS mass > 8 solar masses … explosive nucleosynthesis … MS.

The Deaths of Stars Chapter 10. Mass Transfer in Binary Stars In a binary system, each star controls a finite region of space, bounded by the Roche Lobes.

Chapter 12: Stellar Evolution Stars more massive than the Sun The evolution of all stars is basically the same in the beginning. Hydrogen burning leads.

Stellar Evolution. The whole process takes about 10 millions years. If a protostar forms with a mass less than 0.08 solar masses, its internal temperature.

Announcements Pick up graded homework (projects, tests still in progress) Turn in Homework 10 by 5:00 Vote tomorrow! Transit of Mercury (crossing in front.

Supernova Type 1 Supernova Produced in a binary system containing a white dwarf. The mechanism is the same (?) as what produces the nova event.

Ch. 11: The Deaths and Remnants of Stars (part a) The evolution of intermediate-mass stars. Planetary nebulae and the formation of white dwarf stars. Supernova.

STARS. For most of recorded history the Earth was thought to be the center of the universe and never moved. The constellations were named and stories.

Supernova Type 2 Supernova Produced during the death of a very massive star.

Constraints on progenitors of Classical Novae in M31 Ákos Bogdán & Marat Gilfanov MPA, Garching 17 th European White Dwarf Workshop 18/08/2010.

Survey of the Universe Tom Burbine

Astronomy – Stellar Evolution What is a Star? Stars are hot bodies of glowing gas that start their life in Nebulae.(1) 2.

Nova. Nova – Rapid increase in luminosity of a white dwarf in a binary system The Roche lobe is the region of space around a star in a binary system within.

Charles Hakes Fort Lewis College1. Charles Hakes Fort Lewis College2.

Lifecycle Lifecycle of a main sequence G star Most time is spent on the main-sequence (normal star)

A Star Becomes a Star 1)Stellar lifetime 2)Red Giant 3)White Dwarf 4)Supernova 5)More massive stars October 28, 2002.

Clicker Question: In which phase of a star’s life is it converting He to Carbon? A: main sequence B: giant branch C: horizontal branch D: white dwarf.

1 Supernova By: Courtney Lee and Matt Tanaka. Supernova An explosion of a massive supergiant star. An explosion of a massive supergiant star. One of the.

Ch Stellar Evolution. Nebula—a cloud of dust and gas. 70% Hydrogen, 28% Helium, 2% heavier elements. Gravity pulls the nebula together; it spins.

Star Life Cycle Review. Transports energy from the radiative zone to the surface of the sun. Sunspot Corona Photosphere Convective zone.

9. Evolution of Massive Stars: Supernovae. Evolution up to supernovae: the nuclear burning sequence; the iron catastrophe. Supernovae: photodisintigration;

Red Giant Phase to Remnant (Chapter 10). Student Learning Objective Describe or diagram the evolutionary phases from the beginning of stellar formation.

Progenitor stars of supernovae Poonam Chandra Royal Military College of Canada.

Bell Ringer 10/13 Why do we celebrate Columbus Day?

Death of sun-like Massive star death Elemental my dear Watson Novas Neutron Stars Black holes $ 200 $ 200$200 $ 200 $ 200 $400 $ 400$400 $ 400$400.

The Star Cycle. Birth Stars begin in a DARK NEBULA (cloud of gas and dust)… aka the STELLAR NURSERY The nebula begins to contract due to gravity in.

Death of Stars. Lifecycle Lifecycle of a main sequence G star Most time is spent on the main-sequence (normal star)

The Deaths of Stars Please press “1” to test your transmitter.

Chapter 12: Stellar Evolution. Most stars spend a majority of their lives (~90%) on the main sequence (about 10 billion years for our Sun) Virtually all.

Supernova Type 1 Supernova Produced in a binary system containing a white dwarf. The mechanism is the same (?) as what produces the nova event.

Novae and Supernovae - Nova (means new) – A star that dramatically increases in brightness in a short period of time. It can increase by a factor of 10,000.

What have we learned? What does our galaxy look like? – Our galaxy consists of a disk of stars and gas, with a bulge of stars at the center of the disk,

Stellar Evolution Chapters 16, 17 & 18. Stage 1: Protostars Protostars form in cold, dark nebulae. Interstellar gas and dust are the raw materials from.

Stellar Evolution – Life of a Star Stellar evolution is the process in which the forces of pressure (gravity) alter the star. Stellar evolution is inevitable;

Medium mass star (e.g. Sol). Nebula Cloud of gas and dust (“gust”)

On The Fate of a WD Highly Accreting Solar Composition Material Irit Idan 1, Nir J. Shaviv 2 and Giora Shaviv 1 1 Dept. Of Physics Technion Haifa Israel.

Death of sun-like Massive star death Elemental my dear Watson Novas Neutron Stars Black holes $ 200 $ 200$200 $ 200 $ 200 $400 $ 400$400 $ 400$400.

Star Formation - 6 (Chapter 5 – Universe).

Formation of Stars - 3 (Chapter 5 – Universe).

Stellar Evolution Pressure vs. Gravity.

Stellar Evolution Chapters 16, 17 & 18.

Death of Massive Stars / Exam Prep

Goals Explain why stars evolve Explain how stars of different masses evolve Describe two types of supernova Explain where the heavier elements come from.

Astronomy – Stellar Evolution

Intrinsic in⋅trin⋅sic

The Deaths of Stars.

Life Cycle of a Star.

Stellar Evolution Chapters 12 and 13.

Presentation transcript:

An ancient nova shell around the dwarf nova Z Camelopardalis Michael M. Shara, et al. 2007, Nature, Vol March 鹿豹星座

Contents Cataclysmic variables [Classical nova (nova) and Dwarf nova] GALEX observation around the dwarf nova Z Cam (Camelopardalis) Connection classical nova and Dwarf nova

Classical Nova (L~10 5 L sun ) The classical nova outburst arises from a nuclear explosion in the surface layers of a white dwarf When about M sun of of hydrogen-rich matter has been accreted from the companion (red- dwarf), temperature and the density is enough large so that a nuclear explosion. Typical time intervals between outbursts are several ten thousand years. Typical time intervals between outbursts are several ten thousand years.

Dwarf Nova The matter accumulates in the accretion disk until an instability develops The entire accretion disk crashes down onto the white dwarf and large amounts of gravitational energy are released. Within weeks to months, a new accretion disk forms, becomes unstable, and the outburst is repeated. Within weeks to months, a new accretion disk forms, becomes unstable, and the outburst is repeated.

A prediction including all dwarf novae a classical nova. The accretion of a sufficiently massive shell onto a white dwarf in any cataclysmic binary, including all dwarf novae, is predicted to inevitably generate pressures large enough to initiate a thermonuclear runaway and hence a classical nova. (Shara, M.M.A., 1981)

Z Camelopardalis (Z Cam) Z Cam is one of the brightest and of the closest (~163 pc) dwarf novae in the sky.

NASA UV telescope GALAX observed Z Cam and its surroundings GALAX revealed, for the first time, an arc UV-emitting material with a radius r~15 arcmin (SW), and linear nebulosities (NE and SE) This nebulosities material are interpreted as the ejecta produced by historical classical nova.

Spectroscopic observations HαHα [N ‖ ] [O ‖ ]

Shocked ionized shell Density of the Shell →, wheres is expected from the conventional theory. Shock thickness → arcmin Total mass of the shell →

Classical nova origin? If the classical nova origin, the most contribution on the mass of shell must be the gathered ISM. →Nova model predicts an ejected envelope for 1 solar mass white dwarf. ● The observed range of the velocity of the matter recently appeared novae is which gives an age of the shell, ● If real age is >1000, there would be no historical record. ● This young age also is consistent with the present location of Z cam with the proper motion.

Others ? 1.Wind ejected from the Z Cam system during the dwarf nova ? 1.A remnant planetary nebula ejected by AGB star, which is now white dwarf ? Mass loss rate Expected age of the shell Displacement due to its proper motion

including all dwarf novae a classical nova. The accretion of a sufficiently massive shell onto a white dwarf in any cataclysmic binary, including all dwarf novae, is predicted to inevitably generate pressures large enough to initiate a thermonuclear runaway and hence a classical nova. (Shara, M.M.A., 1981)