Laboratory characterization and astronomical detection of the nitrosylium (nitrosyl) ion, NO + Stéphane Bailleux University of Lille June 18, 2014 – 69 th ISMS Meeting

Atmospheric NO + D- & E- regions of the ionosphere ( 60 – 130 km )  NO + and O 2 + : most abundant ions (Dalgarno & Fox, 1994)  photo–ionization (UV + X–rays) of N 2, NO, O 2  low exothermicity : major source and sink of other species (N, O, NO) Significant IR emitter in the thermosphere : N + + O 2 → NO + (v) + O O + + N 2 → NO + (v) + N EnviSat satellite / MIPAS spectrometer (40 – 170 km) 38 r o-vibrational lines (López-Puertas et al, 2006)

Astro-chemistry of NO + NO (X ² Π ) detected in :  Sgr B2 (Liszt & Turner, 1978)  L134N (McGonagle et al, 1990)  Orion–KL, W33A, W51M (Ziurys et al, 1991) NO + in space if T sources < 15 K  Herbst & Klemperer (1973), Alberti & Douglas (1975)  Pickles & Williams (1977), Singh & Maciel (1980) Many N–bearing species detected, e.g. HCN, HNC, NO, HNO, … NH 3, N 2 H +, NH 4 +, … CN (–), C 3 N (–), C 5 N (–), … NO/H 2 ~ 10 –8

Molecular properties First ionization energy of NO : eV Reactivity : X 1 Σ + (close-shell) isoelectronic with CO, N 2 I ( 14 N) = 1 ⇒ quadrupolar (hyperfine) structure  stable r e exp = Å ( r NO ≃ 1.15 Å) µ ≃ 0.36 D

Spectroscopy of NO + Electronic emission : A 1 Π – X 1 Σ + J = 1 – 0 : ~ ± 30 MHz (Alberti & Douglas, 1975) NO + in Ne matrix (Jacox & Thompson, 1990) fundamental vibrations (cm –1 ) : 14 N 16 O + : N 16 O + : N 18 O + : Hi–resolution spectroscopy  IR (diode laser) : 8 transitions  MMW : 2 lines (Bowman, Herbst & De Lucia, 1982) J = 2 – GHz + hyperfine structure ( 14 N) J = 3 – GHz

Extended negative glow discharge to pump N2N2 LN 2 solenoid pressure gauge NO or N 2 + O 2 anode 320 MHz  10 MHz PLL feedback   IF GHz local oscillator ~10 MHz Ref. oscillator 10 MHz Rb atomic clock Phase Sensitive Detector InSb Oscilloscope phase modulation BWO pre- amplifier LN 2 -cooled absorption cell ballast 5 kV /8 mA BWO power supply

Laboratory measurements vJ’ ( 14 NO + ) ( 15 NO + ) (15) (120) (40) (40) (50) (50) (60) (50) (80) (60) (75) (50) J = 1 ← 0 triplet not observed ( 14 NO + v = 0) MHz (F = 1 ← 1) MHz (F = 2 ← 1)F = J + I N MHz (F = 0 ← 1)

Bowman et al. (1982) cm –1 14 NO +

Constants (MHz) NO + 14 NO + 15 NO + our workBowman et alour work rotation B0B (6) (16) (8) D0D (6) (1) (7) B1B (9) (2) D1D (9) B2B (64) D2D (13) quadrupole eQq (40) (10)

IRAM 30 m telescope (Pico Veleta, Spain) Line surveys  3, 2 & 1 mm 198 kHz resolution  3 mm 50 kHz resolution

Target : cold, dark core B–1b (1200 M ☉ ) 1 st detected in B1–b : HCNO, CH 3 O, NH 4 +, NH 3 D + D–fractionation : NH 3 D +, ND 3, D 2 CS, … rich chemistry in B1–bB1–b : helps understanding star formation 2 very dense cores N(H 2 ) = cm –2 n(H 2 ) = 10 5 cm –3 T = 12 –15 K Molecular clouds in Perseus © Adam Block

2 velocity components 6.5 km s –1 : cm – ² 7.5 km s –1 : cm – ² 6 hyperfine components (6.5 km s –1 ) NO + J = 2 – V LSR (km s –1 ) Predicted line profile from a model with 2 velocity components O NLY NO + MATCHES THIS LINE IN THE M ADEX C ODE (4900 SPECIES )

NO + J = 2 – GHz HCNO J = 4 – 3 HSCN J = ³/₂ – ¹/₂ F = ⁵/₂ – ³/₂ NO MHz J K a K c = 1 01 – 0 00 HNO new species NOHNO X NO / X NO + ≃ 510 X NO / X HNO ≃ 550 X NO + / X HNO ≃ MHz MHz

Time–dependent gas–phase model 1117 species 1117 reactions Pathways in cold, dense clouds charge transfert : H + + NO → NO + + H ion – molecule : N + + CO → NO + + C proton elimination : H + + HNO → NO + + H 2 dissociative recombination : NO + + e → N + O

model : typical dark cloud n(H 2 ) ≃ 10 5 cm –3 T ≃ 10 K X NO + pred ≃ X NO + obs X NO pred ≃ 4  X NO obs X HNO pred ≃ 150  X HNO obs Abundance relative to H 2 Time (yrs) Predicted abundances

only 1 line detected no satisfactory chemical formation path matches the low observed HNO abundance better models needed (reactions at the surfaces of grains, …) Interstellar species containing N and O poorly studied Concluding remarks

Co–authors E. Alekseev (Inst. Radio–Astronomy, Karkhov) J. Cernicharo & B. Tercero (Dep. Astrophysics, Madrid) A. Fuente & R. Bachiller (Obs. Astronomy, Spain) E. Roueff & M. Gerin (Obs. Paris–Meudon) S. P. Treviño–Morales (IRAM, Spain) N. Marcelino (NRAO) B. Lefloch (Inst. Planetologie & Astrophysique, Grenoble, Fr)

Y 10 (  e ) (3)cm –1 Y (1)cm –1 U 01 / µ µµ (5)MHz Y 01 (B e ) (5)MHz  01 N (2) Y 11 ( -  e ) (2)MHz Y (  e ) (5)MHz Y 02 ( - D e ) (9)kHz Y 12 2 (  e ) (10)kHz Dunham analysis ( 14 N 16 O + ) E v,J / ℎ = ∑ Y lm (v + ½ ) l J m (J+1) m Y 01 = U 01 / µ (1 + m e  01 N /M N ) U 01 (r e BO ) ² = (36)   r e BO = (5) Å

Complete spectrum (1.7 GHz)